I wonder, though, whether you’ve defined such a possibility out of existence, by stipulating that the PSR is and must be true, so that the idea of a thing without a reason is already impossible. — J

Yes, I think that is the very point of the PSR. By making a thing without a reason impossible, by definition (actually 'by law', the law being that principle), we do not consider the possibility of a thing which has no reason. Such a thing has been outlawed. Therefore, the enquiring (philosophical) mind will not be discouraged from seeking the reason for things, when the task gets tough, and something appears to be without a reason. The possibility that it really is without a reason has been outlawed so that we do not get discouraged in this way.

I guess I’m not sure whether you’re offering this connection of reasons with what can be known as a demonstration that the PSR must be true, or as an entailment of what must follow if the PSR is true. — J

The PSR "must be true", to support the philosophical mind, and the desire to know. If we allow that it may not be true, then we allow that we may become discouraged from the task of expanding knowledge to cover all of reality, and then designate particular things as occurring without reason. That is an unreasonable point of view to the philosophical mind with the desire to know.

BTW: There’s a provocative book called No Way: The Nature of the Impossible, edited by a mathematician and a physicist, that collects instances of the debate over what’s possible (including in epistemology) from a wide variety of disciplines, from medicine to music. With a question as big as this, it’s really helpful to hear from people who’ve encountered the problem in a specific situation related to their expertise. Well worth finding a copy if you can. — J

I'll keep that in mind.

Folk can Google it, Meta. Cheers. — Banno

Yes, folk can Google it. But I referred to serious philosophers, and Google does not do the studying for serious philosophers. So again, your claim is irrelevant. At least you are consistent in irrelevance.

I think the point he's driving for is that for a philosopher, the term is ridiculous. It's a totally reasonable and real physics thing though. I suggest his point is irrelevant anyhow, But this seemed to me the crossed purpose there. "instantaneous" doesn't hold it's standard meaning in that phrase. — AmadeusD

Correct, a misuse of the term. We all know that velocity is always an average and therefore no velocity is ever properly "instantaneous". Any measurement of velocity is derived from at least two instants. Banno however, seems to actually believe (or at least argues for) the literal meaning of "instantaneous", just like he seems to believe that what are termed "logical possibilities" are not actually treated as the necessities of modal logic. It appears to be a matter of Banno simply assuming that a word has a specific meaning, without taking the time to adequately understand what the word really means, within the context which it is used.

If you're now (it seems you are) making a physics argument, I have to just say you're wrong. This is a physics concept that is widely understood as extant and helpful to physicists. If your gripe is with the use of hte word 'instantaneous' fine, but that's not how the word is used in that phrase. It is a proper name, for all intents and purposes, and so your reading is simply inapt. In any case, the term 'instant' does not mean "zero time" unless you're using a rather unsophisticated colloquial definition. "a very short period of time" is the better way to think of the word, and solves your usage issue regardless of your disagreement with the facts of the matter (i.e that instantaneous velocity is a real, measurable thing which physicists use every day).

Perhaps he was away from school the day "tangent" was taught.

We cannot accurately portray it as "a first principle" because it consists of a number of principles which are applied. We can describe human beings as using logic, and use that as a first principle, i.e. human beings use logic. — Metaphysician Undercover

I believe the first three laws of logic combined, "a thing is what is it, not what it is not, and there is no in-between", constitute the first principle. The other laws of logic, like modal logic, are sub-branches of this first principle, much like the laws of causality are sub-branches of the PSR.

Logic is not only a first principle of epistemology (i.e. deduction) but also of metaphysics. This is why we can speak of possible worlds. E.g. a four-sided triangle is a contradiction and thus cannot exist in any possible world.

we could restrict the meaning of "logic" to deduction, and class the other two in a broader category, as reasoning, along with deductive "logic" as a different form of reasoning. — Metaphysician Undercover

Yes, I'd prefer to restrict "logic" to deduction to clearly differentiate it from the other two types of reasoning. This leaves the other types of reasoning, induction/abduction, to be associated with the PSR, because they aim to find the best or most sufficient explanation to account for the data, i.e., they appeal to the PSR. Then, the general term that covers all types can indeed be called "reasoning".

if we place severe restrictions on "logic", we cannot say "everything must necessarily be logical", then we exclude the things which are understood by other forms of reasoning. — Metaphysician Undercover

We must clarify a possible confusion here. Things can be non-logical (they can be reasoned without deduction but with induction/abduction instead) but not illogical (they violate the laws of logic). Thus, inferring the existence of a fire from the existence of smoke is not strictly speaking "logical" because the smoke could be caused by something else, but it is also not "illogical" like inferring the existence of something that is both a fire and not a fire.


With that, since both deduction and induction/abduction are first principles of epistemology, and these types of reasoning appeal to logic and the PSR respectively, then correspondingly, both logic and the PSR are first principles of metaphysics.

So the question is, how would we be able to determine that there is no reason for something. If we cannot find the reason, or even judge ourselves as incapable of finding the reason, that does not mean that there is no reason. — Metaphysician Undercover

I suppose we could identify every possible cause of a given outcome and eliminate them by testing them individually. But this could still leave room for a possible non-physical cause that could not be identified in the field of physics.

Total non sequitur. — AmadeusD

Can you point to where, in the conversation between me and MoK, there is a non sequitur?

But life is possible whatever the laws of nature are! — MoK

Why? There are possible worlds in which there is no life. Why not possible worlds in which life is not possible?

Even if that is true, it is also true that not all laws of nature exist in all possible worlds. So the laws of nature for a given possible world are designed. — A Christian Philosophy

Pretty clear this does not follow.

is correct.

Your understanding of necessity is nonexistent. — Metaphysician Undercover

Fine.



Can there be a necessary being? The answer turns on whether you’re working within S4 or S5. Let’s map this out carefully and then draw a reasoned conclusion.

Here's the difference:
S4:
Axioms:
□p → p (if necessarily p, then p)
□p → □□p (if necessarily p, then necessarily necessarily p)
Accessibility relation: transitive, but not necessarily symmetric.

◇□∃x does not entail □∃x.
The system is more modestly modal: it allows nested possibilities without flattening them.
Therefore, even if a necessary being is possible, it doesn’t follow that it necessarily exists.


S5:
Axioms:
Everything in S4
Plus: ◇p ↔ □◇p
Equivalent to: □p ↔ ◇□p
Accessibility relation: equivalence relation (transitive, symmetric, reflexive).

If it's possible that a necessary being exists (◇□∃x), then it must necessarily exist (□∃x).
This is the core move in Plantinga’s modal ontological argument; if God (as a necessary being) is possible, then God exists necessarily. So in S5, possibility implies necessity in this special modal sense. This is too strong, allowing the modal collapse of possibility into necessity.


So:
If S5 is correct, and if a necessary being exists, then everything that exists does so necessarily.
But this erases modal distinctions and makes contingency illusory. Therefore, even if a necessary being exists in S5, the result is metaphysically unstable or unattractive — not because the being itself is suspect, but because necessity becomes bloated and indiscriminate.

If S4 is correct, a necessary being may exist without collapsing contingency. But since S4 lacks the machinery to promote possibility to necessity, we cannot infer the existence of such a being from modal possibility alone. Thus, the modal route to a necessary being is blocked.

Either way, there are profound problems for necessary beings.

Its in the specific section i've quoted. The conclusion that 'design' is involved is a non sequitur. Banno also noticed this.

To clarify, the OP only aims to defend the existence of intelligent design, not the existence of a necessary being. Having said that, I accept your demonstration that Plantinga's ontological argument is not valid. So, if we were to defend the existence of a necessary being, we'd need to use another argument.

Even if that is true, it is also true that not all laws of nature exist in all possible worlds. So the laws of nature for a given possible world are designed. — A Christian Philosophy

I think you mean that the last sentence in the above comment does not follow from the first sentence alone. I agree, but it was in reference to the whole discussion with MoK, not in reference to this comment alone.

To clarify, the OP only aims to defend the existence of intelligent design, — A Christian Philosophy

And what exactly is intelligent design? As to any "necessary" being, that requires some rigor in definition. People, for example, appear to be the result of processes: are the processes intelligent? Imho, neither "design" nor "intelligent" are useful terms, being in fact deceptive and misleading. There is neither intelligence nor design, only the progress of processes. Of course if you would like to believe that you are intelligently designed, and only possible through the agency of a super designer, you are free to do so.

But if you want it to be real, then make it real. Show it, prove it, demonstrate it.

If you're now (it seems you are) making a physics argument, I have to just say you're wrong. This is a physics concept that is widely understood as extant and helpful to physicists. If your gripe is with the use of hte word 'instantaneous' fine, but that's not how the word is used in that phrase. It is a proper name, for all intents and purposes, and so your reading is simply inapt. In any case, the term 'instant' does not mean "zero time" unless you're using a rather unsophisticated colloquial definition. "a very short period of time" is the better way to think of the word, and solves your usage issue regardless of your disagreement with the facts of the matter (i.e that instantaneous velocity is a real, measurable thing which physicists use every day). — AmadeusD

I agree about this difference in the meaning of "instantaneous". But Banno does not accept that difference of meaning, and equivocates in his complaints about my explanations. This is a common, recurring problem I have with Banno, which became evident when I demonstrated that he equivocates with the use of "same" in his interpretation of Wittgenstein's private language argument. Instead of acknowledging the tendency to equivocate, Banno doubles down and makes fun of my arguing technique.

Notice that's exactly what Banno was attempting in this thread. Instead of looking at defining "necessary" in a rational, intelligent and meaningful way, as I proposed, Banno attempted to change the subject to discuss modal logic, which excludes "necessary" to some ideal Platonic realm. This leaves "necessary" without any practical import. But then, Banno will continue to use "necessary" in the normal, practical way, while insisting on that ideal definition. That is equivocation.

So in he case of "instantaneous", there is an ideal "instant" which refers to an assumed point in time. I say it's assumed because time flows, and there is no real point in time. So that point in time, the "instant" is an ideal only. In practise, in physics with the use of calculus, a person might determine an "instantaneous velocity". Of course, that so-called "instantaneous velocity" is really the velocity over a period of time, because the instant in time is an ideal, and the accuracy of the determination is dependent on the parameters of the calculation.

For a simplified example, suppose I take a five second period of time, and determine that the velocity of an item in that time period was 5m/s. I could insist that at every "instant" of time in that five second period, the item had that 5m/s velocity. But of course that would be meaningless, and actually false. An "instant" in this sense is an ideal only, so it is meaningless when applied toa physical object, and it is false because I determined the five second period, and divided it evenly, assuming another ideal, perfectly constant motion. Of course that is a simplified example but it applies to accelerated and decelerated motions as well, which assume constancy.

Now we have the same sort of situation in this thread. Banno wants an ideal definition of "necessary", which he represented with "MUST". Of course such an ideal form of "necessary" does not enter into any practical application, just like the ideal "instant" does not enter into the practise. The important point is that just like with the mathematics, we may represent the ideal, and claim that it enters into the practise, with the mode of representation employed, but this claim is actually meaningless and false. The real form of "necessary" which enters into our practise of logic is our decisions as to what is "necessary for", or needed for, our purposes. And this varies according to the situation and principles applied, just like the meaning of "instantaneous" varies according to the application.

Logic is not only a first principle of epistemology (i.e. deduction) but also of metaphysics. — A Christian Philosophy

I would disagree with this, placing metaphysics as necessarily prior to logic. The reason for this, is that as we come to understand the nature of reality it becomes apparent that there are aspects which escape the applicability of those primary three laws. Aristotle described this class of aspect as "potential", and matter is placed in this category. His solution was to allow for a violation of the third law, excluded middle, to accommodate for what may or may not be. The problem is deep though, because the proposal of "prime matter", pure potential, violates the law of identity, because pure potential could not have any form therefore no identity. Aristotle rejected the proposal of "prime matter" in his metaphysics, but if we accept that proposal, then we also allow violation of the second law, noncontradiction, by avoiding identity. This is the case with dialectical materialism, and dialetheism.

So the issue is that we need to adapt our principles of logic to conform to our understanding of reality, and this is why metaphysics is commonly placed as prior to epistemology. The conventional approach has been to produce forms of modal logic, and these roughly follow Aristotle's lead, as exceptions to the third law, being systems to deal with possibility. Notice that I say "systems", plural, because there is a number of possible ways to approach the reality of possibility. This is why metaphysics must be understood as prior to epistemology, because we need principles to choose which system of logic is applicable to the circumstances.

E.g. a four-sided triangle is a contradiction and thus cannot exist in any possible world. — A Christian Philosophy

This exemplifies the problem of definition. The truth of this statement requires a specific definition of "triangle". Someone could propose a possible world in which "triangle" is defined as four-sided, and this possibility renders your statement as false. So that statement places the definition of "triangle" as something completely outside the system of logic, and somehow fixed, thereby creating the necessity of "thus cannot exist in any possible world".

Clearly this is a false necessity, because words can be defined as we please. So in classical logic, definitions enter into the system, being premises, and the necessity is created by acceptance of the definition. So your example really requires another premise, which would define "triangle" as three sided, and by that premise, a four-sided triangle is excluded.

With that, since both deduction and induction/abduction are first principles of epistemology, and these types of reasoning appeal to logic and the PSR respectively, then correspondingly, both logic and the PSR are first principles of metaphysics. — A Christian Philosophy

I agree with this, but the problem is to determine which principles are applicable in which circumstances. This is where metaphysics and epistemology interact. Take your example, someone sees smoke, and concludes that there is fire where the smoke is. If the person used the premise "where there is smoke there is fire", this would be a deductive conclusion. Therefore by your definition the conclusion is logical. However, we can see falsity in the premise, and in the formulation of the premises is where we find the nuances of reasoning.

If we have found fire in every situation that we have found smoke, we still cannot derived the certainty required for "necessary", as explained by Hume. So the truth of inductive premises escapes the certainty for "necessary". Further, we have to look at what "every situation" means. If the person has only seen smoke twice, and each time there is fire, this clearly is insufficient to support the premise. Furthermore, we sometimes loosen up the rules to accept probability. Perhaps seeing fire associated with smoke 99% of the time allows one to accept the premise. Also, there are nuances within the description of "smoke" which need to be considered. A person might have noticed that black smoke is always associated with fire, and white smoke often has no fire, and so the person might be using a more nuanced premise. In short, there are many factors involved in the creation of a premise, and unless the premise is a simple definition, necessity is not provided for. And even with a definition, the defining terms are not themselves defined, because this would produce an infinite regress, so necessity is not absolute even in the case of definition.

I suppose we could identify every possible cause of a given outcome and eliminate them by testing them individually. But this could still leave room for a possible non-physical cause that could not be identified in the field of physics. — A Christian Philosophy

Yes of course, this is the base of the problem, and why dualism forms the foundation for many metaphysicians. There is a fundamental difference between efficient causation which is studied by physics, and final causation which is studied in social studies, and by metaphysics. Since there is a gap between the two, meaning that we do not understand how one acts on the other, the designation of "every possible cause" is sort of meaningless or misleading. The PSR allows for both principal types of cause as "the reason". So if we determine "every possible cause" of the physical type, and are inclined toward concluding 'no reason', this still does not exclude the possibility of a cause of the non-physical type. Therefore the PSR gives us encouragement to keep on seeking the reason for an occurrence even after it has been proven that there is no physical cause for it.

Fine. — Banno

Good, we agree on something. That gives us a starting point. Care to join me on a learning experience, or is it too late to teach an old dog like yourself, new tricks?

but claim physics doesn't "experience" time... and does nto "know" time. what does that mean? — Banno

By experience, I mean a conscious event that contains information. By know, I mean being aware of through observation, inquiry, or information. Generally, the physical does not have the capacity to know. Even if we grant this capacity for the sake of argument, it cannot know the correct time that the causation is due to, since it does not experience time.

And there is an odd jump from "the physical in the state of S1 cannot cause the physical in the state of S2" to "physical cannot be the cause of its own change". I don't understand what that phrase is trying to do. — Banno

Most people have difficulty seeing how P3 follows from P2. C follows from P3. By "physical cannot be the cause of its own change" I mean that the change in physical assuming that it is due to cause and effect cannot occur.

Define, please. I believe you are tangled up in various meanings of this word. — tim wood

By experience, I mean a conscious event that contains information, such as percepts, feelings, thoughts, etc.

Even if that is true, it is also true that not all laws of nature exist in all possible worlds. — A Christian Philosophy

How do you know?

So the laws of nature for a given possible world are designed. — A Christian Philosophy

That does not follow from the previous statement.

Why? There are possible worlds in which there is no life. Why not possible worlds in which life is not possible? — Banno

I assume that all possible worlds are infinite in size. Of course, if a possible world is finite in size, then life may not be possible within the world.