Knowing something doesn't imply that it's impossible to be wrong, by the way.

And if you thought of knowing that way, then, for example, you'd have to say that in terms of the sciences, we categorically can never know anything, because it's a basic tenet of science methodology that any claim is open to revision in the face of new evidence. In other words, it's a basic tenet that any scientific claim could be wrong. It's never impossible that a scientific claim is wrong. Taking a claim so that it's impossible that it can be wrong means that we're no longer doing science.

But obviously, the vast majority of people do not use "know" that way--we know many things in the sciences.

And then you get those silly Gettier problems. — T Clark

The Gettier problems primarily hinge on the notion that intuitively, people do not want to say that we can know something accidentally.

But the Gettier cases, in my and some other folks' views, typically hinge on misconceived ideas of how the actual contents of belief work with respect to formal logical conventions.

Assign a factor to the epistemological reliability of your credible witness? God's validated word is 1.0, your credible witness is given a prior of .8. The contention then is that your state of knowledge of this fact is, itself, approx. .8. — JosephS

Well.... Two thoughts - First, I don't really like a numerical calculation like this for decision making, although it is not uncommon in my line of work. Example - we put a design out to bid. We establish a set of criteria for the bids, say price, experience of bidder, quality of technical approach to the work, completeness of the proposal, health and safety performance in past projects, company size and resources. Then we weight the criteria by importance. As you might imagine, price gets the highest weight. Then we rank each criteria, multiply by the weighting, and then add up the values. Bidder with the highest ranking gets the project. Problem - it almost never works. We almost never pick the company we think will do the best job.

Second - As I said, you can't really know your "state of knowledge" unless you take in to account the consequences of failure. The question isn't how much uncertainty is there in my decision, it's whether or not the justification is adequate given the risk. The question to ask - what could possibly go wrong.

Totally agree. And I have gotten so much shit over the years for saying the T should be taken out. First, because it implies that there are two criteria for knowledge 'justification and truth. When in fact, there is no second process after evaluating the justification where we then look to see it is true. If we have evidence of a black swan, then the justification that there are lots of white ones is poor justification. When we evaluate the justification we will look for counerexamples and lack of logic, but we cannot determine now if in the long run what we consider true today will be true tomorrow. Adding the true is confused. — Coben

As I've said, I think you also have to take the consequences of failure into account. If the decision is who has to wash the dishes, who really cares. If it's should we start a war in Iraq, we have to be a lot more careful. We found out what could possibly go wrong with that. Now the people in the White House are itching to do the same thing in Iran.

Negative justification is trickier than positive justification. Furthermore, positive justification deals with the physical world where we can look at the world and draw conclusions. Negative justification is lack of evidence and is much weaker. — Noah Te Stroete

In the context of my approach to knowledge - justification takes in to account certainty, benefits, negative consequences) - then negative evidence is important. If I have searched carefully for negative evidence and haven't found any, that contributes in a major way to justification.

And if you thought of knowing that way, then, for example, you'd have to say that in terms of the sciences, we categorically can never know anything, because it's a basic tenet of science methodology that any claim is open to revision in the face of new evidence. In other words, it's a basic tenet that any scientific claim could be wrong. It's never impossible that a scientific claim is wrong. Taking a claim so that it's impossible that it can be wrong means that we're no longer doing science. — Terrapin Station

This brings to mind a relevant quote from Stephen Jay Gould that I've always loved:

“In science, ‘fact’ can only mean ‘confirmed to such a degree that it would be perverse to withhold provisional assent.’” Replace "fact" with "knowledge."

Oh no, more agreement. Yes, different things would demand different degrees of justification.

Oh no, more agreement. — Coben

Yeah, we both must be wrong.

Or....there is some subtlety hidden in the negation that escapes me, and the whole OP actually has some epistemic value. — Mww

Maybe my title was confused. I’m not sure now. I don’t have a lot of confidence in that.

I was thinking that if truth is a requirement of knowledge, then happening to correspond with actual states of affairs in reality cannot be fully known (or certain or proved).

Truth is conditioned by thought, knowledge is conditioned by possibility; both are conditioned by time. I don’t see as one will ever be a requirement for the other. Not all truths are known and not all knowledge is true.

On the other hand, I know I detest Lima beans, so it is absolutely required that it be true Lima beans be something in order for me to know I detest them. When I was 6 it was 18 steps from my bed to the bathroom. When I was 16 it was 14 steps from my bed to the bathroom. The truths and the knowledges of each set of circumstances are exactly the same, but not so are all the states-of-affairs.

One can talk about truth, or one can talk about knowledge, for days. But trying to put them together is a whole ‘nuther can of metaphysical worms.

Truth is conditioned by thought, knowledge is conditioned by possibility; both are conditioned by time. I don’t see as one will ever be a requirement for the other. Not all truths are known and not all knowledge is true.

On the other hand, I know I detest Lima beans, so it is absolutely required that it be true Lima beans be something in order for me to know I detest them. When I was 6 it was 18 steps from my bed to the bathroom. When I was 16 it was 14 steps from my bed to the bathroom. The truths and the knowledges of each set of circumstances are exactly the same, but not so are all the states-of-affairs.

One can talk about truth, or one can talk about knowledge, for days. But trying to put them together is a whole ‘nuther can of metaphysical worms. — Mww

You’ve given me a lot to think about.

Truth is conditioned by thought, knowledge is conditioned by possibility; both are conditioned by time — Mww

Could you flesh this out for me so I can understand it better?

On the other hand, I know I detest Lima beans, so it is absolutely required that it be true Lima beans be something in order for me to know I detest them. When I was 6 it was 18 steps from my bed to the bathroom. When I was 16 it was 14 steps from my bed to the bathroom. The truths and the knowledges of each set of circumstances are exactly the same, but not so are all the states-of-affairs. — Mww

I think this helps explain your first paragraph, but I would need more of a demonstration or explanation with more examples to fully understand it. That is up to you whether you want to, of course.

Opinions might not be the best way to properly understand much of anything.