My analysis would actually be closer to the second than the first, and I largely agree with ↪Sam26's reply, though I framed it differently. The basic idea is that some "why?" questions misfire because they try to put into question that which makes questioning possible in the first place. Framed like this, it can be seen as a retorsion argument, or argument from pragmatic contradiction. — Esse Quam Videri

I agree. Some “why?” questions misfire because they try to question what makes questioning possible in the first place. In that sense the move is retorsion, a pragmatic contradiction: it borrows the norms of justification while attempting to place the background that makes those norms operative on trial. The key is to keep the point limited to that kind of global “why?,” and not treat it as a dismissal of ordinary, practice-governed activiity for reasons aimed at epistemic certainty.

You’re right that my view is that Gettier trades on an impoverished picture of justification, and that the guardrails and the “+U” are meant to show what our practice already treats as decisive, not to bolt on a fourth condition. I find it amazing that people find Gettier significant.

On your second question, by “the core intuition” I mean the feeling that makes Gettier cases grip us:

The belief is true.

The subject can qbite supporting considerations that look like justification.

Yet the truth shows up by luck, because the support is fragile, or dependent on a false ground, or insulated from the mistake-conditions the practice recognizes.

That’s why we resist calling it knowledge, even though it can look like JTB is met on the surface.

This is not rare. It happens a lot in ordinary life because most of what we call knowledge isn’t absolute certainty. We’re usually dealing with epistemic certainty, defeater-resistant stability in practice, and in many domains that stability is unavoidably probabilistic.

My diagnosis isn’t just relabeling. It’s an attempt to explain why the Gettier intuition arises so often: we mistake surface marks of support for justificatory standing. Once you make explicit the ordinary constraints that already govern standing, No False Grounds, Practice Safety, and Defeater Screening, the Gettier case stops looking like a refutation of JTB and starts looking like a case where the belief was true, but the route was lucky or too fragile to count as knowledge.

If you keep “adequate justification,” you haven’t really escaped JTB, you’ve just renamed it, and you’ve made key distinctions harder to state.

“Adequate justification” still presupposes a target. Adequate for action isn’t the same as adequate for knowledge. If you collapse knowledge into “what I’m willing to act on,” you turn epistemic standing into risk tolerance. Two people with the same evidence can differ just because they’re more cautious. That’s prudence, not knowledge.

The so called JTB trappings are the distinctions you still need. Truth is about how things are, belief is what the subject holds, justification is the belief’s standing. If you throw those out, you end up rebuilding them anyway to explain the difference between “I acted responsibly” and “I knew.”

Your engineering language already matches my guardrails. QA/QC is No False Grounds. Standards of practice are Practice Safety. “Don’t ignore known failure modes” is Defeater Screening. The real question isn’t JTB versus adequacy. It’s whether “adequate” stays vague, or whether you spell out the failure modes that make a belief look supported when it isn’t.

Discarding JTB doesn’t remove Gettier, it relocates it. If knowledge is “adequately justified true belief,” you still need to exclude lucky truths. Either you tighten adequacy to rule out luck, which is exactly what Practice Safety and defeater sensitivity do, or you let luck count as knowledge.

The only place I'd put up a little flag would be when you speak about "the ordinary criteria as illegitimate in advance" as a sign of hinge-questioning doubt. This problem goes back to Descartes, and is outside the scope of your OP, but I would make the case that Cartesian methodical doubt doesn't actually posit anything as illegitimate in advance, and neither does the skeptic in our example. In both instances, the skeptic is really raising a question about certainty, not about some subject. No genuine doubt is being expressed -- existential doubt, I might call it -- concerning two-handedness. Doubt is wielded as a tool to sculpt certainty, to learn how far the whole method can be pushed before we have to cry "I can conceive of no further doubt!" — J

From a Wittgensteinian standpoint, I still can’t make sense of the Cartesian maneuver as doubt. Doubt isn’t a free-floating posture you can apply to anything at will. It’s a move inside a practice, and it only makes sense where there are criteria for what would count as checking it, correcting it, or settling it. When you try to doubt everything at once, you don’t get a deeper form of doubt, you remove the background that gives “doubt,” “test,” and “justification” their role in the first place.

That’s also why it helps to keep my four senses of certainty explicit: subjective certainty (conviction), hinge certainty (what stands fast and makes inquiry possible), epistemic certainty (defeater-resistant stability in practice), and absolute certainty (logical or moral necessity). Ordinary, practice-governed justification aims at epistemic certainty. Cartesian doubt pushes toward absolute certainty, and it treats hinge certainties as if they were ordinary claims waiting for ordinary support. From the Wittgensteinian angle, that isn’t a legitimate extension of doubt, it’s a shift in the grammar of the activity.

The issue isn’t that the skeptic declares ordinary criteria illegitimate. The issue is that the exercise changes the kind of question being asked, and once it does that, it stops looking like genuine doubt within a practice and starts looking like a philosophical performance aimed at an impossible standard.

The point of my paper (the paper this thread is based on) was to strengthen traditional JTB with Witt's later philosophy.

So what happens if we ask "Why?" about the justification of such a statement? We might give two analyses. In the first, which I think is yours, we'd say, "The question is meaningful, and admits of an answer. It may be the case that no satisfactory answer presents itself, but that is not the question's fault, so to speak. The fault lies with us (with philosophy), in our inability to provide a deep enough explanation." In the second, which uses the hinge idea (if I understand it), we'd say, "This sort of 'why?' takes us outside of what it means to look for a justification. There's no satisfactory answer because the standpoint from which the question can be meaningfully asked presupposes the conceptual (Sam would say 'grammatical') equipment needed to ask it."

That said, I lean more toward the first analysis than the second. Is it possible to doubt whether I have two hands? Yes. Do we know the general sorts of things that justify our (comparative) certainty about two-handedness? Yes. Perhaps Sam can go on to elaborate the ways in which "the usual patterns of justification and doubt" are resisted. To me, it seems equally possible that we are simply more certain about two-handedness. — J

I think you’ve set up the contrast well, but I’d adjust one thing. My view isn’t that the first “why?” is always meaningful and the second is always meaningless. The point is that the word “why?” can function in more than one way, and we have to look at what’s being asked.

There’s a perfectly ordinary “why?” about “I have two hands (as Witt points out),” and it does admit of familiar answers: perception, memory, proprioception, photographs, other people’s reports, medical records, and so on. That’s all inside the practice, and it’s exactly the sort of thing I mean by practice-governed justification.

The hinge point shows up when the “why?” is no longer a request for more evidence, but a request to put the whole practice of checking on trial at once. In that mode, the question isn’t “what justifies my belief that I have two hands,” it becomes “what justifies the entire framework in which perception, memory, testimony, and correction count as checks at all.” That's when the demand starts to misfire, not because we are too stupid to answer, but because the request is asking for a kind of justification that cannot apply to the role the background plays.

When you say you lean toward the first analysis, I think I mostly agree, provided we keep the second analysis available for a particular sort of escalation. It's not that hinge talk denies that we are simply more certain in some cases. It's that in some cases the certainty isn't just a higher degree of ordinary confidence. It's functioning as a stopping point for the practice, something that is shown in how we proceed.

On your question about “the usual patterns of justification and doubt” being resisted: one way to mark it is this. In ordinary doubt, there are recognizable defeaters and recognizable tests. If I doubt whether the bus comes at 9, I know what would settle it. In hinge cases, the demand for justification either has no settled criteria of satisfaction, or it treats the ordinary criteria as illegitimate in advance. That's a sign we have shifted from a local “why?” inside the practice to a global “why?” that tries to step outside the practice while still borrowing its tools.

I’d put the point like this: sometimes we are simply more certain, and we can cite ordinary supports. But sometimes the “why?” is being used in a way that attempts to make the whole background answerable as if it were an ordinary claim, and that's where hinge talk earns its keep.

The importance of testimony isn't just how it relates to the resurrection argument, but it's important across a wide range of domains even in science

Post 6: Number

“Number” matters in testimony, but only when it means independent lines, not just a large headcount or a story repeated many times.

In ordinary life, testimony gets stronger when multiple witnesses report the same event independently, through different channels, with the possibility of cross checking. But when many reports trace back to the same source, the “number” can look large while the evidential base stays narrow.

So here’s the question for the resurrection: How many independent lines of testimony do we actually have, once we separate sources from repetition?

A few quick ways to keep this honest:

Lists aren’t automatically independent. A later summary that reports “many people saw” doesn’t give us many independent reports, it gives us one report about many.

Multiple documents don’t automatically mean multiple lines. If documents share a tradition, depend on one another, or arise from the same inner circle, the apparent number can outpace the real independence.

Sincerity doesn’t add independence. A community can sincerely repeat what it inherited without adding new evidential weight.

If someone’s Christianity doesn’t rise or fall on a bodily event in history, then my argument won’t work in the same way, because it’s aimed at the attempt to treat that event as knowledge on the basis of testimony.

I think that's backwards. You call it "the traditional concept of knowledge," but it doesn't match how normal, everyday people use the word in their normal, everyday lives. Everyone knows we can't be absolutely sure of what we know before we act. So we do the best we can. In that context, JTB implies that every time anyone has made a mistake in the past what was knowledge then magically turns into not knowledge now. That means that "knowledge" is meaningless, valueless, pointless. That's the only intractable I can think of--the impossibility of knowing whether I know something. And it's not really intractable, it's just silly. — T Clark

I agree with your everyday point, i.e., nobody in ordinary life assumes absolute certainty before acting, and any account of knowledge that required that would be unlivable. But I don’t think JTB, as I’m using it, commits us to that.

The “magically turns into not knowledge” worry comes from treating knowledge as if it had to be indefeasible. In ordinary practice, we don’t talk that way. We say, “I knew, given what I had,” and we also say, “I was wrong.” Those aren’t contradictions. They mark two different evaluations: what was justified at the time, and what we now know after a defeater has arrived.

A mistake doesn’t make past knowledge meaningless. It shows that justification is fallible and defeasible, which is exactly how everyday epistemic life works. What changes, when new information comes in, is not that the past was magic, but that the belief no longer has standing now, because the practice has acquired a defeater.

That’s also why my guardrails matter. They’re not demanding absolute certainty. They’re making explicit the constraints we already use to separate knowledge from lucky success and from fragile support. Defeater screening, in particular, is not a demand to foresee every possible counterexample. It’s the ordinary discipline of not ignoring live alternatives and known failure modes.

And on your last line, “the impossibility of knowing whether I know,” I’d put it this way: we don’t need a guarantee that we know in order to know. We need justificatory standing that’s good enough for the domain or context and the stakes, and we need openness to correction when real defeaters appear. That’s not silly, that’s exactly what “knowing” looks like in ordinary life.

Can you name a hinge you think my framework relies on, and say whether you think it should stand fast or be challenged.
— Sam26

Maybe this: You/we take it to be certain that the role of understanding in human consciousness is significant, that it makes a difference, that it is a desideratum quite separate from knowledge. To be skeptical about understanding – to say something like “You can’t prove to me that what you call understanding has any effect on what I say and do” -- is a kind of undermining, as you describe, since it seems to demand the very framework which it calls into question. But I’m not sure about this; so many skeptical challenges can be interpreted not as questioning a hinge proposition but simply as demonstrating that our language allows us to ask “Why?” about pretty much anything.

At the very least, we find ourselves with a problematic involving the concepts of knowledge and understanding – perhaps that is a kind of hinge. I can’t justify my certainty that this pairing is both necessary and in tension, but nor can I imagine how to do any philosophy at all without taking it to be so, much less use the concept of "justification". — J

I think you’re close.

I’d just tighten the hinge, so it isn’t framed as a claim about human consciousness, as if it were an empirical thesis. In my use, the hinge is more grammatical than psychological: that “understanding” is a real difference in our epistemic practices, not a decorative word. We already operate with a distinction between someone who can recite the right justification and someone who can track mistake-conditions, defeaters, and correction. If you remove that distinction entirely, the practice of calling anything “justified” starts to lose its point.

I agree with you that a radical skepticism about understanding has a self-undermining flavor. It isn’t merely another “Why?” within the practice (or form of life), it targets what makes the “Why?” game intelligible in the first place. Of course, language lets us ask “Why?” about almost anything, but that doesn’t mean every “Why?” is the same kind of request. At some point the request stops being a demand for reasons inside the practice and becomes a demand for the framework to justify itself by the very tools the framework makes possible.

Your last paragraph also lands with me. There’s a genuine problematic, knowledge and understanding belong together and can be in tension. I don’t treat that as a conclusion I prove. I think of it as part of the background against which my project makes sense at all. That’s exactly the kind of thing I mean by a hinge, not a dogma, but a standing fast that is displayed in how we proceed.

Post 5: Variety

Conviction can spread even when the evidence is thin. One of the things that keeps testimony from collapsing into group reinforcement is variety.

By variety I mean diversity in the lines of testimony: different contexts, different audiences, different pressures, and different routes of transmission. In ordinary life, testimony is stronger when it doesn’t all come through the same social channel or the same interpretive community. Variety matters because it helps separate what’s being reported from what’s being carried along by shared expectations and shared identity.

So here’s the question for the resurrection: Do we have genuinely diverse and independent streams of testimony, or do we mainly have one community preserving and repeating its own founding story?

Volume isn’t variety. Repetition isn’t independence. And a single community can preserve a tradition and also shape it, even when nobody is trying to deceive. When the same circle supplies the report, the meaning of the report, and the setting in which it’s repeated, the conditions for drift are present.

I know this is a different strand, but I don’t understand how the resurrection is supposed to be useful in the first place. Let’s assume it is true. Why would an immortal god enact a primitive blood sacrifice and ruin a weekend just to free people from rules he himself created? Why not simply appear and set people straight? It seems unnecessarily convoluted: if the goal is to guide or save humanity, there are far clearer ways to communicate or intervene. The story reads less like a practical solution and more like a patchwork of old religious myths woven into a narrative. — Tom Storm

The resurrection is supposedly God's stamp of approval on Jesus, that he's God. It's also supposed to solve the problem of sin, etc.

There are plenty of reasons someone might reject Christianity besides the weakness of the testimonial evidence. For instance, why would an omniscient God create human beings knowing in advance that many would reject him and end up in hell? That isn’t a small side issue. It raises a moral and philosophical problem about divine goodness and foreknowledge, and it forces Christians to explain why a world with that outcome the world is a perfectly good and all-knowing creator would choose to bring into existence.

Post 4: Consistency

Conviction can be sincere and stable, but sincerity doesn’t settle standing. One of the things that strengthens testimony is consistency, not in the sense of word for word agreement, but in the sense of stable convergence on the features that matter.

I’m not arguing that every discrepancy makes a report false. Real witnesses differ. They notice different details. They tell the story differently. In ordinary life, that doesn’t automatically discredit testimony. The question is what the differences look like, and what they do to the claim’s ability to stand without constant repair.

So, here’s the question for the resurrection: Do the accounts substantially converge on the crucial features without requiring harmonization to make them fit?

A few clarifications so we don’t talk past each other:

Consistency isn’t sameness. I’m not looking for identical phrasing. I’m looking for stable agreement on the load bearing elements: what happened, to whom, where, when, and in what kind of mode.

Some differences are minor, some aren’t. Differences about incidental details may not matter much. Differences about the structure of the event, the nature of the appearances, the timing, or the witness list do matter, because they affect what kind of claim is actually being made.

Harmonization is not the same as convergence. If the accounts need to be combined, smoothed, or reinterpreted so they can be made consistent, that itself tells us something about the strength of the testimony. Strong testimony usually doesn’t need a later strategy of repair to keep it stable.

Legend is a live alternative here. Not “fraud,” not “mass delusion,” but ordinary development over time as stories are told, retold, and shaped to carry meaning. Consistency, in the relevant sense, is one of the things that can block the “legend” drift. If the record doesn’t block it, then “legend” remains a serious contender.

So, I’m putting the question plainly: when we read the resurrection accounts, do we find a stable, convergent core that stands on its own, or do we find a pattern that requires later stitching?

Even granting a stable core, “Jesus died, the followers proclaimed he was raised, and there were claims of appearances,” the consistency question turns on what happens when we ask for recoverable particulars. When we move from proclamation to narrative detail, the resurrection tradition shows a pattern of variation that matters, who goes to the tomb, what is encountered there, what is said, where the appearances are centered, and the sequence of events. These aren’t merely stylistic differences, because they shape what kind of claim is actually being made and how well it can stand without later stitching. None of this proves fabrication. But it does mean that the testimony, as it has reached us, is less able to block the ordinary alternatives, development over time, legend drift, interpretive reshaping, without relying on harmonization to stabilize it. And when the claim being asked to stand is a bodily resurrection, that dependence on repair is a weakness under the consistency criteria.

Forgive my meandering response. From what I read, that all seems fair and seems to come down to “a book says a thing”. I wonder though, even if there were a couple of witnesses would this resolve the matter? How would we establish, centuries later, if a given witness is truthful or mistaken?

As I said on a different thread, isn’t it generally understood that, resurrection aside, there are no eyewitness accounts of whoever it was who inspired the Jesus story? Was it one person or more than one? Or are the mythicists right in saying it is all fictional? I am inclined to think there may have been some historical origin to the story. But it's accepted that Muhammad was a real historical person, and that does not mean he literally cut the moon in two or rode a flying horse.

The Gospels were written many years after the events they describe by anonymous authors and survive only as copies of translations of earlier copies. The names attached to them were applied later by church tradition. I was taught this, not by atheists, but by Christian lecturers, who were not fundamentalists.

You know the old C. S. Lewis “Liar, Lunatic, or Lord” argument? many have found it interesting that he left out a fourth option: Legend. — Tom Storm

Thanks, it's not meandering, it’s actually very close to the point of the thread.

You’re correct that, at a certain level, we’re dealing with texts, and you’re also right that “a couple of witnesses” wouldn’t automatically settle anything centuries later. That’s exactly why I’m not treating this as a courtroom fantasy where we just add two affidavits and call it knowledge. The question is whether the kind of testimonial support we have, taken as a whole, is strong enough to bear a bodily resurrection claim. And part of what makes it hard is what you said: we don’t have direct access to witnesses, we have chains of transmission.

On the mythicist question, I’m not going to make that the center of this thread, because it’s a different argument. You can grant a historical Jesus and still deny that the resurrection testimony reaches justificatory credibility, the Muhammad story is such an example. A real founder doesn’t make miracle reports automatically credible. So, I’m not relying on “Jesus wasn’t real.” I’m asking whether the testimony for a bodily resurrection is strong enough even if we assume some historical origin.

On the Gospels, the anonymity and the gap in time matter here, not because “anonymous” means “false,” but because it complicates firsthand character, traceability, and corroboration. If we can’t identify the witness layer with confidence, and if our documents are late and mediated, then the testimony is structurally less able to meet the ordinary tests of reliability and correction. Again, not a refutation by itself, but it’s a real constraint on how much standing the claim has.

And yes, the “Legend” option is relevant. It’s one of the ordinary alternatives that testimony has to be able to resist if it’s going to rise above conviction. Legends don’t require fraud. They require time, transmission, interpretive pressure, and communities that preserve meaning even when details shift. That’s why my approach isn’t “liar” or “lunatic.” It’s: what does the testimonial record look like, and does it have what we need to treat a claim like this as known? My answer would be no.

Post 3: Corroboration

Conviction can be sincere and widespread, but that doesn’t give a claim justificatory standing. Corroboration is one of the main things that does.

By corroboration I mean independent confirmation, support that doesn’t just repeat the same report in another form. In ordinary life, testimony becomes strong when it isn’t trapped inside a single chain. When different lines converge, especially lines that don’t share the same incentives, the same community pressure, or the same source material, then testimony starts to earn standing.

So here’s the question for the resurrection: What independent corroboration do we have for the central claims, corroboration that doesn’t depend on the same Christian tradition simply restating itself?

A few clarifications so we don’t talk past each other:

Repetition isn’t corroboration. If one text depends on another, or if multiple accounts draw from the same underlying tradition, we may have multiple tellings, but we don’t yet have independent confirmation.

“The Church says so” isn’t corroboration. It may explain how belief was preserved, but it doesn’t supply an independent check on whether the event occurred.

Later belief doesn’t corroborate the original event. A movement can grow quickly and still be wrong about what happened at its origin. Growth can show conviction and social power. It doesn’t, by itself, confirm the event.

Hostile or neutral sources matter here. In ordinary cases, corroboration is strongest when it comes from sources that aren’t invested in the claim, or even resist it. That doesn’t mean they have to agree with everything, but it means the report is exposed to pressure that can correct it.

So I’m putting a straightforward challenge on the table:

What independent corroboration do we have that Jesus’ tomb was found empty?

What independent corroboration do we have that multiple people, in different contexts, experienced bodily appearances, rather than visions, dreams, or interpretive experiences?

What independent corroboration do we have for the timing and circumstances, beyond the internal Christian reporting itself?

If your answer is that the corroboration is mostly internal, that’s not an automatic refutation. But it is a diagnostic feature. It means the resurrection claim is being asked to stand on a narrow evidential base, and that makes the other criteria, firsthand character, consistency, variety, and number, carry far more weight than they would in an ordinary case.

I discuss hinges in a paper located here: https://thephilosophyforum.com/discussion/8443/an-analysis-of-on-certainty/p31

Scroll down to the paper titled Wittgenstein's Hinges and Gödel's Unprovable Statements.

Post 2: Firsthand Character

Conviction is always present in a system of beliefs, but conviction alone isn’t enough to justify a belief. In other words, sometimes people claim to know, but this use of "I know..." is not epistemic, it's an expression of a conviction.

In my last post I laid out five criteria for strong testimony. I’m going to start with the one that matters most here: firsthand character.

In ordinary life, testimony is strongest when we can say, with some clarity, who is reporting, what they claim to have experienced directly, and how that report reached us. The point isn’t that secondhand testimony is always useless. We rely on it constantly. The point is that as the claim becomes more weighty, and as the event becomes more unusual, the difference between “I saw” and “someone said” starts to matter a lot. And it matters even more when the chain between the event and our sources is long.

So here’s the question for the resurrection: How much of our evidence is identifiable firsthand testimony, and how much of it is tradition about what others claimed to see?

A few observations to keep the discussion focused:

Paul is early, but he isn’t giving us direct eyewitness narratives of the events in Jerusalem. He gives a summary of what he “received” and “passed on,” plus his own claim that he experienced an appearance. That matters, but it isn’t the same thing as multiple named eyewitnesses giving independent reports we can examine.

The Gospel narratives are our main source of appearance stories, but the witness layer is hard to isolate. They’re written as narratives, not as signed statements from named witnesses. Even if they preserve earlier testimony, the question remains: how much of that testimony can be traced and identified as firsthand, rather than as communal tradition shaped in the process of transmission?

When Christians say “there were eyewitnesses,” what do we actually have access to? Do we have the witnesses themselves, their independent reports, and the conditions that normally allow cross checking? Or do we have later reports about witnesses?

Even if we grant, for the sake of argument, that the Gospel accounts are firsthand, that concession barely strengthens the case. Firsthand character is only one criterion. A firsthand report can still be weak if it comes to us through an opaque chain, if it can’t be cross checked by independent lines, and if the normal mechanisms of correction are missing.

And the stakes here matter. In ordinary life, two or three reliable witnesses may be enough for an everyday event, especially when the event fits comfortably inside what we already know about the world. But the bodily resurrection of a dead man is not an everyday event. The claim carries far more weight than the cases where we’re content with a thin testimonial base, and that means the supporting testimony has to carry more of the stabilizing features we ordinarily rely on: independence, corroboration, and exposure to correction.

None of this proves the resurrection false. But it does locate the issue. Christianity asks this testimony to bear an enormous load: the bodily return of a dead man. If the evidence is going to reach the level of knowledge rather than conviction, the firsthand character of the testimony matters, and it matters in combination with the other criteria.

:up:

I appreciate how you’re keeping the placement of understanding in view. You’re right about the distinction that matters most: the dialogic or interactive piece is a method of assessment, not an additional condition of knowledge. It’s simply one of the ordinary ways practices distinguish genuine standing from borrowed standing, sometimes by dialogue, sometimes by performance under new data, sometimes by a task that exposes whether the competence is real.

On whether to expand on the traditional construal of justification, I think a forum audience can be assumed to know the basics. I can probably limit it to one clarification: justification is often treated too thinly, as if it’s exhausted by citeable supports, and that makes it easy to confuse the appearance of support with justificatory standing. The “+U” is my way of preventing that slide.

On “grammar,” I accept the point. The term’s accurate for Witt readers but it can feel like jargon. If I keep it, I should consistently translate it as “criteria for correct use, error, and correction in a practice,” which is what I mean anyway.

I’m glad Practice Safety landed as doing work beyond defeaters and beyond generic reliability talk, that’s exactly why I separated it. On linguistic training, I hear your hesitation. I keep it explicit to remind us that being trained into criteria and rule following is itself a genuine source of standing, even if it often operates in the background of the other routes.

On hinges, I agree the topic can swallow the thread. For my purposes I’m not using hinges to close inquiry, but to mark a structural point: reasons and evidence operate against a background, and not everything that stands fast stands fast as a conclusion. If Nagel’s way of keeping the situation problematic is what helps here, I think that can sit alongside my use of hinges, because my target’s confusion about what sort of thing a hinge is, not an attempt to end reflection.

I probably won't be contributing much to this thread, but . . . you do know that millions of people call themselves Christians today who don't believe in the bodily resurrection of Jesus, despite Paul? Are they mistaken to do so, according to you? Or is it possible that your version of what Christianity involves is too traditional, given the very active, living presence of this religion in our culture? I wonder how many contemporary liberal and progressive Christian theologians you've actually read. — J

Thanks for the comment. You’re right about the sociological fact: many people today call themselves Christians who don't believe in a bodily resurrection. I’m not denying that, and I’m not trying to argue against every Christian belief system.

My point is narrower. I’m taking “Christianity” in the sense that is historically and doctrinally central to the tradition’s own proclamation, and on that point Paul’s conditional matters. If someone treats the resurrection as symbolic or non-bodily, they may still find Christian practices and moral teaching meaningful, but they’ve shifted the kind of claim being made. That shift is precisely what I’m trying to keep visible. It doesn’t settle anything by itself, but it changes what needs to be justified. A metaphor doesn’t require the same testimonial support as a claim about what happened in history.

So no, I’m not saying liberal or progressive Christians are “mistaken to do so” in a moral sense. I’m saying that if the claim is no longer a bodily event in history, then the question I’m asking in this thread isn’t aimed at that version of Christianity. This thread is about the bodily resurrection as a historical claim, because that’s the version that is most often defended as something that can be known and proclaimed as fact.

And I agree that liberal and progressive theologians are part of the living landscape. But notice what their move often is: they reduce the evidential burden by relocating the claim, from “this happened” to “this means,” from event to symbol, from history to existential interpretation. That may be a coherent religious posture, but it’s no longer a claim that stands or falls on testimony in the same way. In that sense it supports my framing rather than refutes it.

I want to explain more about the guardrails, which add constraints to justification within a practice.

Guardrails and the Discipline of Justification

The five routes describe the ordinary ways in which justification proceeds. They show how a belief can be supported within our language-games, through testimony, inference, sensory experience, linguistic training, and the boundary-setting role of pure logic. Yet a route is not, by itself, a guarantee that a belief has the standing required for knowledge. A belief can travel along one of these routes and still fail to count as knowledge because something in the justificatory situation does not have the right shape.
This is why it is helpful to make explicit a set of guardrails, not as additions to the classical model, but as clarifications of what our practices already require when we speak carefully. These guardrails articulate constraints that belong to justification as it functions within a practice. Their point is grammatical (Wittgensteinian grammar). They mark what it is for justificatory support to count as support within a language-game, rather than as something that merely looks supportive from a distance.

I call these guardrails No False Grounds, Practice Safety, and Defeater Screening.

I've explained some of this already, but I want to reiterate it so that it's easier to understand. I'll do this in a series of short posts.

I don't disagree with your Wittgensteinian analysis as to what forms meaning. I just don't see Wittgenstein as offering a methodology for creating definitions. He tells us what meaning is.

If you want a one sentence summary: the Wittgensteinian element is not communal voting, it is the insistence that justification has a grammar of correct use and correction, and once we make that explicit, many Gettier intuitions are revealed as cases where the support was only apparent.
— Sam26

This suggests a Wittgensteinian impossibility, which is that "justification" currently fails to adhere to usage derived meaning , so we need to regulate this rogue term by insisting it follow Wittgensteinian protocol so we can dissolve Gettier issues.

Meaning is use even for terms we wish had better usages.

That is, per Wittgenstein, justification has a grammar whether we insist upon it or not. He's describing the way words obtain meaning. If "justification" has a fragile use where its meaning fluctuates, then that is what it means. We can't "insist" the word have a better meaning to avoid Gettier cases and that then become its meaning unless our insistence changes its community use. But that's not a Wittgenstein issue. That's just step 1, wanting a new definition, and Step 2, implementing that definition however it's done. — Hanover

I think your Wittgenstein point is right, and it helps me say what I am, and am not, claiming.

I'm not treating Wittgenstein as offering a methodology for manufacturing definitions, and I'm not proposing that “justification” is a rogue term that fails to have a grammar until we regulate it. Meaning is use, and “justification” already has a grammar whether we legislate it or not.

What I'm doing is different. I am trying to make explicit features of the existing use that are often left implicit, and then to use that clarified grammar to diagnose why Gettier cases feel forceful. In other words, I'm not saying, “we should insist on a better meaning.” I'm saying, “look at what we already do when we call something justified, and notice the constraints that are already operating.”

In ordinary practice, we already distinguish between a person who can recite supporting considerations and a person who can track mistake-conditions, defeaters, and correction. We already withdraw claims when new defeating information comes in. We already treat certain routes as too fragile for knowledge, and we tighten standards when stakes rise. Those are not reform proposals. They're part of the lived grammar of justificatory talk.

So where does Gettier fit. The Gettier phenomenon arises when we let the surface marks of justification substitute for justificatory standing, and then we are surprised when the belief is true by luck. My claim isn't that we should redefine “justification” to avoid that surprise. My claim is that the surprise shows a mismatch between two things that our practice already distinguishes: seeming to have justification and actually having it under the practice’s own mistake-conditions and defeater sensitivity.

On your final point, you are also right that if a community’s use is genuinely unstable, then that instability is part of the meaning. But that isn't the situation I think we're in with “justification.” The use isn't arbitrary, and it's not merely fluctuating. It's stable enough to underwrite our ordinary distinctions between support, error, defeat, and correction. What fluctuates is often our philosophical picture of what justification must be, for example, thinking it is exhausted by a list of cited reasons, or thinking it must amount to infallible certainty. My project is aimed at dissolving that picture by returning to how justificatory standing actually functions in practice.

So I agree with the Wittgensteinian constraint. I am not legislating a new definition. I'm clarifying the one we already live by, and showing that once the lived constraints are made explicit, Gettier cases stop looking like a deep refutation and start looking like cases where the support was only apparently in order.

I wonder if this suggestion is Wittgensteinian at heart or whether it just seeks an agreed upon justification methodology. That is, would it be incompatible for someone who held meaning is attached to private states to demand an agreed upon methodology as you have here. And contrawise, would it be non-Wittgensteinian to allow for subjectively based justifications? I would think not so long as the meaning was tied to use such that the community of speakers could follow how the term was used and engage in the practice.

So what this boils down to is how to avoid Gettier cases, which do seem to arise from reasonable evaluations based upon incomplete knowledge. Your idea seems straightforward: force a community based standard for what constitutes a justification to avoid poor reasoning and perhaps require deeper investigation before declaring "knowledge."

If you tell me you're coming to my house, I see a blue jeep coming toward my house, you own a blue jeep, I say I know you're on the way, and you then arrive moments later to my house, we can say that I had knowledge of your arrival of the JTB variety. But then we learn it wasn't your jeep I saw and you took the bus, now we have a broken J, and a Gettier problem.

If you mean to add to the J methodology a stricter confirmation of all facts to avoid sloppier individualized justifications, that could be a solution, but I ask why that invokes Wittgensteinian other than perhaps reference to community involvement, but, as noted, the community could still use the word justification to mean whatever it decided without concern for avoiding Gettier.

That is, Wittgenstein wouldn't care whether a term were more useful. He'd only insist it's meaning were derived from use. — Hanover

I do think the framing is Wittgensteinian, but not because it appeals to “community agreement” as if justification were whatever a group votes into existence. The Wittgensteinian point I'm borrowing is about grammar: what makes a claim of justification intelligible is that it's answerable to standards of correct and incorrect application, and those standards are exhibited in a practice, in how we check, correct, and withdraw claims when error signals appear.

On “private meaning,” I'd put it this way. A person can have private experiences, and can have subjective certainty (e.g., a conviction about a belief), but if the meaning of the terms involved were tied only to private states, then the distinction between correct and incorrect use would collapse. You could still demand an “agreed methodology,” but it would be unstable, because there would be no shared criteria to tell whether the methodology was actually being followed or merely seemed to be. That's why, in my framework, justification is not a private experience. It is practice-governed standing, and it is “objective” in the modest sense that the criteria for support, error, defeat, and correction can, in principle, be stated and applied within the practice. This is not consensus, not social permission, and not institutional authority, it is answerability to criteria.

That doesn't make subjectively based justification illegitimate. It means that subjective support has to be connected to use and to criteria that others can follow. If I say “I see blue,” or “I remember,” those are first-person claims, but they still live inside practices with mistake-conditions and correction, misperception, lighting, memory distortion, and so on. I'm not excluding subjective sources. I'm saying that their justificatory standing depends on how they are embedded in standards of assessment.

Now to Gettier. I'm not trying to avoid Gettier by requiring stricter confirmation of all facts. That would be impossible and it would smuggle in an infallibilist demand. The point is different: Gettier cases arise because we treat “seems justified” as if it were the same as having justificatory standing. In your blue-jeep example, what fails is not simply that you lacked a further fact, it is that the apparent support was not connected in the right way to the truth-maker, and the route is lucky. The practice would normally treat that as a fragile inference, and it would tighten the standards when the stakes are higher.

My proposal is not “let the community define justification however it likes.” It's: if we are using the word “justification” at all, we are already committed to certain constraints, no false grounds, practice safety, and defeater sensitivity, because those constraints are built into how justificatory talk functions in our life. Wittgenstein would not tell us to adopt a more useful vocabulary, but he would help us see what our vocabulary already commits us to when we use it.

If you want a one sentence summary: the Wittgensteinian element is not communal voting, it is the insistence that justification has a grammar of correct use and correction, and once we make that explicit, many Gettier intuitions are revealed as cases where the support was only apparent.

I'm no engineer, but it might look something like the following:

No False Grounds (NFG) = “Are we building on bad inputs?”
This is your QA/QC point. It asks whether the data or the key assumptions are incorrect in a way that would make the conclusion questionable.

Examples: wrong sample, mishandled sample, wrong method, transcription error, the lab did not follow procedures, etc.

Practice Safety = “Is the method we used a safe, normal way to reach this kind of conclusion?”
This is closer to standard of practice. It is not perfection, it is “we used a route that usually catches mistakes.”

Examples: proper calibration, chain of custody, replication, using accepted modeling procedures, etc.

Defeater Screening = “Even if the data are good, is there something that would overturn the conclusion?”

This is the part that is easiest to miss, because it happens after you think you are done.
It is the deliberate search for “what would make this conclusion fail.”

Examples in your setting:

A different source could explain the same contaminant pattern.

A missing geological feature changes the direction of some flow.

Seasonal changes that would modify an important consideration.

Another dataset (borings, field observations, historical site use) conflicts with the story you are telling.

So in one line:

NFG: inputs are not false.

Practice Safety: the route to the conclusion is not fragile.

Defeater Screening: no overlooked “gotcha” would overturn the conclusion.

That is how your quality program maps into my epistemology. That's the best I can do not being an engineer. It's just a matter of getting use to the procedure. Engineering has these procedures built into their conclusions.

I'll probably start a separate thread on that subject Tom. I'm not going to get into this subject here, but later in another thread. I'll just say this, most of the testimonial evidence is secondhand (hearsay), so by definition it's weak.

Isn't the annunciation of knowledge itself bound to the character of a localised hermeneutic. Do you give the least weight to individual or subjective testimony? Where is the rationale for weighted significance in your system for each or a combination of what you term, 'routes'? — Alexander Hine

Yes, the annunciation of knowledge is always situated in a local hermeneutic, a language, a practice, a way of drawing distinctions. I'm not trying to deny that. My point is that this doesn't reduce justification to “mere interpretation,” because within a practice there are criteria for correct and incorrect application, there are recognized mistake-conditions, and there are ways of correcting ourselves when the practice throws up error. The hermeneutic is real, but it isn't the whole story.

On individual or subjective testimony, I do give it weight. Testimony is one of the primary routes by which we acquire knowledge, and that includes first-person reports. The question isn't whether the report is subjective, it's how it stands within the standards that govern testimonial support: provenance, competence, independence, convergence, and defeater sensitivity. A single report is rarely self-authenticating, but it can still carry justificatory standing, especially when it's consistent, detailed, and later supported by independent lines of check.

As for weighting the routes, I'm not assigning a fixed hierarchy. I'm saying that the weight is determined by the case. In a given context we ask: which route is actually doing the work, what would count as a mistake in this domain, what would count as a defeater, and how strong are the correction mechanisms that are available. Then we look for convergence across routes, because that's often what turns a fragile support into stable standing. So the rationale for weight isn't that one route always dominates, but that different practices and different questions demand different standards, and the guardrails, No False Grounds, Practice Safety, and Defeater Screening, discipline whatever routes are in play.

You mean to elucidate for this audience that your project is a taxonomy of scientific method. — Alexander Hine

Not quite. What I am offering is a taxonomy of routes of justification that operate across many practices: testimony, logic, sensory experience, linguistic training, and pure logic in a boundary-setting role. Science is one prominent domain where these routes are integrated and disciplined by unusually strong correction mechanisms, but the taxonomy is not confined to science, and it is not meant to reduce every kind of knowing to scientific procedure.

The purpose is practical: when someone claims knowledge, I want to be able to ask, which route is doing the work here, what standards govern it in that domain, what would count as a mistake or defeater, and do the guardrails hold. That applies to science, but it also applies to ordinary life, history, law, engineering, and philosophy when philosophy is making knowledge claims rather than offering a mere stance.

If you want a quick check, a lot of what I call “knowledge” is acquired by testimony and linguistic training long before anyone does anything recognizably scientific.

I'm currently writing a book Why Christianity Fails using this epistemic model. Specifically, I analyze the testimonial evidence for the resurrection and demonstrate the weakness of the evidence.

From my paper:

Much of the contemporary discussion treats Gettier’s paper as showing that JTB is insufficient. I do not think this is the right lesson. The examples do not undermine the model itself. They depend on a confusion between what looks justified on the surface and what is genuinely justified within a practice. Once we attend to the structure of justification, including its graded and fallible character, it becomes clear that these cases fail to satisfy the justification condition in the first place. They rest on false grounds or on a lack of the relevant conceptual competence, and so they fall outside the classical model rather than threatening it. Seen in this way, Gettier does not overturn JTB; it signals the need to make explicit features of justification that the classical formulation left implicit. That is the task taken up by JTB+U in the sections that follow.

Worked Gettier example (diagnostic use). Consider the familiar “ten coins” case. Smith has strong evidence that Jones will get the job, and Smith has counted ten coins in Jones’s pocket. Smith forms the belief, “The man who will get the job has ten coins in his pocket,” by straightforward logical inference from what he takes himself to know. Unknown to Smith, Jones will not get the job. Smith will get the job, and Smith also happens to have ten coins in his own pocket. The belief is true, and it can look well supported, but it does not have the standing required for knowledge.

What fails is not truth, and not belief, but justification. The support Smith relies on depends on what is not the case, namely that Jones will get the job, and this triggers No False Grounds. One can say that Smith’s inference is valid, but validity is not enough, because justification is not merely a logical relation among propositions. It is a standing within a practice, fixed by public criteria that settle what counts as competent support in the context. The same case also brings Practice Safety into view. Smith stumbles into the truth by luck. In ordinary situations where the evidence is similar, he would draw the same conclusion, yet it would be false, so the belief is not practice safe. Defeater screening makes the point plain: once it is determined that Jones may not get the job, the belief loses its standing, and the only repair is to replace the faulty ground. Gettier does not refute JTB, it corrects a picture of justification as a private sense of assurance or a merely formal inference, rather than a public standing fixed by our epistemic practice.

Many acknowledge this, but then when pushed will only rely on science as if it's really the only method/s that counts. This is a confusion even among scientists. The problem is that most people (including scientists) don't have a good epistemology.

Science is not a single justificatory route that replaces the others. It is a practice that braids them together and then tightens the standards of correction.

Testimony: journals, lab notes, instrument reports, datasets, expert consensus, methodological inheritance.

Logic: inference, statistical reasoning, model selection, prediction, and constraint.

Sensory experience: observation, measurement, and interaction with the world through instruments.

Linguistic training: learning how to use the concepts correctly, what counts as a valid operational definition, what counts as a proper classification, what counts as a mistake in the domain.

Pure logic (boundary-setting): coherence constraints, definitional entailments, and the exposure of category mistakes.

Science is distinctive because it tends to force convergence by building systematic error detection into the practice. But the justificatory work still flows through the same routes. That is why it is a mistake to treat “science” as the only path to knowledge, and also a mistake to treat testimony as automatically inferior. The real question is the quality of the route in the case at hand, and whether the guardrails hold.

So you are borrowing from the type of standards that a scientific peer reviewed rationalism would apply to a systemic process philosophy? — Alexander Hine

In my framework, any proposed “method of justification” will usually be describable as a combination of the five routes I listed: Testimony, Logic (inductive and deductive), Sensory experience, Linguistic training, and Pure logic (boundary-setting only). The list is non-exhaustive in the sense that it doesn't pretend to capture every nuance of method, but it is meant to be covering in the sense that methods are built out of these elements, often in combination.

So, when someone proposes a new method, my first move is not to reject it, but to ask: which routes are actually doing the work here, and which guardrails are supposed to discipline them. Many disagreements then become clearer, because they turn out to be disagreements about which route is primary in the case, what the relevant mistake-conditions are, or which defeaters are being ignored.

If you think you have a method that does not pass through any of these routes, I would be interested to see it, but I suspect that in most cases what looks like a sixth method is really a composite that hasn't yet been analyzed under one or more of the methods I've outlined.

When I use the word “justification,” I am not talking about something private, a feeling of confidence, or a mere report of how things seem from a subjective point of view. I mean justificatory standing, the sort of standing a belief has when it is supported by the standards that govern a practice, standards for what counts as evidence, what counts as error, and what counts as correction.
— Sam26

So you mean Doxa? — Alexander Hine

Not doxa in the pejorative sense of mere opinion. I mean the normative standing a belief has when it is entitled by the standards of evidence and correction that govern a practice.

Here is something I stole from a post I made a few years ago.

A site conceptual model is just a description, image of the site which lays out all the information gathered during the investigations. To me, the most useful way of presenting a SCM is visually, using figures. Data tables are also needed. There will also be calculations e.g. groundwater flow direction and velocity, contaminant degradation rates, averages. On the figures, you can show the locations of the sources of the contamination and how it has moved and is presently distributed across the site. You can also show the expected distribution of contamination in the future based on groundwater and fate and transport modelling. You can also show the locations of existing and potential human and environmental receptors.

Typical data points include boring logs; analytical results of soil, groundwater, and sediment samples; visual observation of site conditions; topographic and bathymetric surveys; geophysical surveys; and wetland surveys. Going deeper, there are assumptions associated with laboratory analytical methods. Which in particular are you talking about? — T Clark

This is what I had in mind. A site conceptual model is a perfect case of knowledge that is not best expressed as a single proposition, but as an integrated representation: figures, tables, calculations, assumptions, and forecasts. In my terms, the unit being assessed is not one sentence but a model with correctness conditions, it can be more or less accurate, it can succeed or fail under error signals, and it can be revised when it runs into defeaters.

So, when I talk about justification here, I am not asking you to apply an engineering standard to a bare declarative sentence. I am asking how the SCM earns and keeps justificatory standing in the practice. Your description already points to the routes: sensory observation at the site, measurement and sampling, inference and modelling, testimony in the form of reports and lab results, and linguistic training in the way standards and classifications are applied. The important question is how those routes are disciplined.

That is where the guardrails map cleanly:

No False Grounds: what would count as a false ground in the SCM, a faulty assumption or input that is doing decisive work, for example a mistaken stratigraphic interpretation, a mislocated source term, or an analytical artifact that propagates through the map of contamination.

Practice Safety: what makes the SCM robust rather than lucky, for example triangulation across independent data types, sensitivity checks, conservative assumptions where appropriate, and repeated checks that would expose a fragile inference.

Defeater Screening: what kinds of findings would force revision, for example a new boring log that contradicts the stratigraphy, a plume boundary that violates the predicted hydraulic gradient, or receptor evidence inconsistent with the proposed pathway.

On your last question, I am not asking about one laboratory method in the abstract. I mean the assumptions that bear the weight in the overall chain that supports the SCM.

If justification is a standing within a practice, then understanding is the competence by which a person can genuinely participate in that practice, not merely mimic its conclusions.
— Sam26

I think I've grasped how you use "understanding" here, and why it isn't a fourth criterion for knowledge, but rather an attempt to clarify what justification actually entails. At this point, an example would be helpful. The question of what it means to "mimic the conclusions" is central, I think. You write:

Someone can hold a true belief and even cite a correct supporting data, while still failing to grasp what that support is doing, what would count against it, what would defeat it, and what would count as a relevant correction. In that situation the belief can look justified from the outside, and even to the person themselves, but the justificatory standing is fragile, because the person does not reliably track the mistake-conditions that the practice treats as decisive.
— Sam26

As an example, I picture a student who writes a paper on a topic in science; the paper describes a true belief which the student holds, and cites all the correct data. Why is the student only mimicking the conclusions? Because their understanding of why the data provides a justification has to involve a simultaneous understanding of the conditions under which they wouldn't -- the defeaters, in other words. If the student lacks this understanding, their claim to justification is shaky, and probably false.

Does that sound right? OK, here's the question: If the belief "looks justified" both from the outside (publicly) and to the person themselves (privately), how should we describe the process that will show us it's not justified? It seems as if a verification of understanding requires a further, dialogic process with the one who claims justification (and knowledge). And that's fine, but perhaps you should emphasize the need for this further step. I agree that it still doesn't make for a fourth criterion, but it does seem significantly different from the process we would engage in to learn a person's justifications, which, as you point out, can be merely cited or mimicked. Another homely example might be defending a thesis.

Maybe all of this is to say we can't "vet understanding" in the same way we can vet a proof, or even a proposition. The proof doesn't reply to our questions, but we do require the person to, otherwise we're not in a position to say whether the U part of JTB+U is present. This doesn't contradict your theory in the slightest, just elaborates it a bit, and puts it in a context of Habermasian "communicative action." — J

This is a strong reading of what I meant, and your student example captures the central point. “Mimicking the conclusions” is precisely the case where a person can reproduce the correct outputs, cite the right data, and sound fluent, while lacking a grasp of the mistake conditions, the relevant defeaters, and the revision pathways that the practice treats as decisive. In that situation, the belief can look justified, even to competent observers, because the surface marks of justification are present, but the standing is fragile because it's not anchored in the competence that makes those marks responsibly usable.

Your question about how we show that the belief is not justified is also right, and it helps to make explicit something I left implicit. In many domains we do not vet understanding by inspecting a static artifact alone, as if it were a completed proof. We vet it by exposing the claimant to the practice’s tests, especially its countercases. That often does require a dialogic dimension: questions, challenges, requests for boundary conditions, requests for what would count as defeating information, and requests for how the claim would be revised if those defeaters obtained.

But I want to put this carefully, so it does not look like an added criterion. The “further step” you describe is not a separate requirement piled onto justification, it's one of the ordinary ways a practice determines whether a person has justificatory standing or has only borrowed it. It is the difference between an utterance that happens to be correct and a competence that can carry that correctness across the relevant cases. In that sense, the dialogic process is a method of assessment, not an additional condition of knowledge.

It is also worth noting that the need for dialogue varies by context. Sometimes understanding can be vetted through performance without explicit conversation, for example by reliable error detection, appropriate revision under new data, or correct handling of nearby cases. In other settings the quickest test is indeed oral examination, thesis defense, or cross examination. Either way, the underlying point is the same: understanding is shown in how the claimant navigates defeaters, boundary conditions, and correction, not merely in the ability to cite supporting considerations.

So, I agree with your closing line as an elaboration: we cannot vet understanding in the same way we vet a proof considered as a static object. We vet it by putting the claimant into the space of questions and challenges that the practice treats as intelligible. That is compatible with my view, and I think it helps readers see that “public” does not mean “a pile of citations,” it means susceptibility to the practice’s checks, including dialogic ones when the case calls for it.

If you want a single sentence version of the answer: when a belief looks justified on the surface, the practice distinguishes genuine standing from mimicry by testing whether the person can track defeaters and revise under correction, and that test is often, though not always, dialogic.

I've read all seven of your chapters. Just for workability, I'm going to respond to each chapter separately. This may mean that what I have to say will be a bit disjointed. We'll see.

My biggest overall issue--JTB generally applies to propositions but most of the knowledge we have and use is not really expressible in that form. As an engineer, I usually talked about "conceptual models," which means an overall picture of the situation--in my case it was real estate properties and the soil and groundwater characteristics distributed across the site and at different depths. Models like that will generally be judged and justified as accurate rather than true. As I indicated, as I see it, the way we use knowledge on a daily basis tends to be more like how I've described it rather than just the truth of propositions.

This is highlighted by your discussion of the idea of standards of practice which are used to justify truth. In general, I think that's right, but how standards are applied under JTB (or JTB-U) is different from how various practices apply their standards. How do I apply an engineering standard to a simple declarative statement?

So, I worry that I am going to send your discussion off on a tangent. Now that you've seen some of the substance of my thoughts, should I continue? — T Clark

I don't think this is a tangent, I think it's exactly the kind of stress test that helps clarify my ideas.

On the first point, I agree that a great deal of what we rely on is not best described as a single proposition. Much of it is a competence, a grasp of a situation, a model, or a way of seeing how things hang together. In engineering, the object of assessment is often a conceptual model, and the operative question is whether the model is accurate, robust, and fit for use across the relevant conditions, not whether a sentence is true in isolation.

My reply is that this does not put the JTB family out of business, it forces a clarification of what “truth” and “justification” are doing. A model can be assessed for correctness in the world, it can succeed or fail, it can be refined under error signals, and it can be defeated by counterevidence. In other words, it has correctness conditions even if it's not naturally expressed as a single declarative statement. The “propositional” layer can be treated as a partial extraction from the model, for example, predictions, constraints, and consequences that can be checked. That is often how the model earns and keeps its standing.

On your second point, I agree that we should not imagine applying an engineering standard to an isolated declarative sentence as if that were the primary unit of knowledge. The better way to put it is that standards of practice govern the evaluation of the claim in its proper form, which may be a model, a procedure, a measurement protocol, or a forecast. When I say “public” or “practice-governed,” I mean that there are criteria for correct application, error, and correction that can be articulated and contested within the practice. Engineering seems like a textbook example of this, because the standards include calibration, measurement error, boundary conditions, sensitivity to assumptions, and the discipline of revising the model when it fails.

So, I would welcome you continuing, but with one focusing suggestion so we do not drift. When you respond to a post, pick one concrete engineering example of a conceptual model and say how it is justified in your sense. Then we can map it onto my vocabulary without forcing it into a single sentence: which route of justification is doing the work, what would count as a defeater, where No False Grounds shows up, and what “practice safety” looks like in that domain. If we can do that once, the “propositions versus models” worry will either dissolve or become precise enough to evaluate.

Optional sidebar: Hinges and Gödel, a structural parallel

A brief note for readers interested in foundations. In my paper I suggest a structural parallel between hinge certainties and Gödel style limits. The parallel is not evidential, and it is not a proof of anything in epistemology from mathematics. It is a comparison of structure.

In Gödel’s setting, once a formal system is rich enough, there are truths expressible within the system that cannot be proven by the system’s own resources, and consistency cannot be established from within in the strongest way one might want. The upshot is not that mathematics collapses, but that the practice operates with boundary conditions that are not resolved by the same methods the system makes possible.

In the hinge setting, justificatory practices also have stopping points. Certain things stand fast, not as conclusions of inquiry, but as the background that makes inquiry, doubt, evidence, and correction possible. The upshot is not that justification collapses, but that justification always operates within a framework whose role is not that of an ordinary claim awaiting ordinary support.

So the comparison is this: both domains exhibit limits on what can be achieved from within, and both continue rationally once those limits are acknowledged. That is all I mean by the parallel.

If you want to press on this, I would welcome it, but it will help to keep the debate focused on whether the analogy is illuminating rather than on technical details of Gödel’s proofs.

Much of this is already written out, which is why I can respond quickly sometimes.

Clarifications and terms (so we do not talk past each other)

Before continuing, I want to clarify a few terms that can easily be misunderstood.

What “+U” is and is not. In JTB+U, “Understanding” is not a new ingredient bolted onto JTB. It is a way of making explicit what justification already presupposes in ordinary epistemic practice, the competence to grasp what counts as support, what counts as error, and what would count as correction in the domain.

What I mean by “public.” When I say justification is public, I do not mean popular agreement or institutional permission. I mean that justification has criteria that can, in principle, be articulated, assessed, challenged, and corrected within a shared practice.

Practice Safety is not a demand for infallibility. Practice Safety means that the route by which a belief is held is not fragile or lucky with respect to the mistake conditions the practice recognizes. It is about tracking error signals in the domain, not about achieving certainty in the absolute sense.

What I mean by a defeater. A defeater is not merely disagreement. It is a consideration that, if true, would remove or weaken the support, or would show that the apparent support is misleading. Defeater screening is the discipline of identifying and facing such considerations rather than ignoring them.

Hinges are not reasons. Hinges are not hypotheses supported by evidence. They are background certainties that stand fast and make evidence, doubt, and correction possible in the first place.

Four uses of “certainty.” I distinguish subjective certainty (conviction), hinge certainty (bedrock), epistemic certainty (defeater resistant stability in practice), and absolute certainty (logical or moral necessity). When we disagree, it often helps to say which sense of certainty is in play.

Post 7 of 7:
Gettier, and why “seems justified” can mislead

Gettier cases are designed to make the traditional JTB account look inadequate. The familiar pattern is that a person has a true belief, and can cite what appears to be a justification, yet we hesitate to call it knowledge. The standard moral is that JTB is missing some extra condition. My paper argues that this moral is too quick, because it treats “justification” as if it were exhausted by having a supporting consideration that can be stated.

On the view I am developing, the key distinction is between a belief that looks justified, and a belief that has genuine justificatory standing within a practice. In Gettier style cases, the subject often has support that is either dependent on a false ground, or is insulated from the relevant mistake conditions, or is undermined by an undefeated defeater. In other words, the cases exploit a gap between seeming to meet the justification requirement and actually meeting it once the ordinary constraints on justification are made clear.

This is where the guardrails matter. If a belief depends on a false ground, No False Grounds blocks it. If the route is fragile and the belief is true by luck, Practice Safety blocks it. If there is relevant defeating information that has not been faced, Defeater Screening blocks it. The upshot is not that Gettier reveals a defect in JTB, but that Gettier is trading on an impoverished picture of justification, and once justification is properly described, the cases no longer force an additional condition.

This also brings the “+U” into focus. Understanding is not a decorative addition. It marks the competence by which a person can genuinely track what their support does, what would count against it, and what would require revision. A person can cite a reason and still be out of contact with those mistake conditions. When that happens, the belief can be true and can look justified, yet it lacks the stability we normally require for knowledge.

Upshot: Gettier cases do not show that knowledge needs a mysterious extra ingredient. They show that we should not confuse the appearance of justification with genuine justificatory standing.

Questions for critique:

Do you think Gettier cases still refute JTB even if we build in the guardrails and the “+U” clarification.

Is my diagnosis too dependent on relabeling the justification condition rather than answering the core intuition.

If you have a favorite Gettier case, post it and say which guardrail you think it slips past, if any.