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The metaphysical presuppositions of formal logic

edwardfeser.blogspot.com

91–100 of 114 posts

Re: The metaphysical presuppositions of formal logic

#91
post #13

Earlier quoted context omitted.

"Eternalism" refers to the static "block universe" conception of spacetime, where all events exist simultaneously, past, present and future. "Presentists", by contrast, hold that the past no longer exists, the future does not yet exist and only the present moment exists. Neither are positions about whether there is/was a first moment of time. I just finished reading the physicist Sean Carroll's book "From Eternity to…

Very rarely, physists DO care about logic. For example: https://www.jstor.org/stable/1968621 And: https://en.wikipedia.org/wiki/The_Logic_of_Modern_Physics But given that the first is from 1936 and the second from 1927, maybe that's out of fashion.

> Very rarely, physists DO care about logic.

Some physicists are interested in quantum logic – that is very much a minority taste within the physics community though. Like interpretations of quantum physics in general, it straddles the boundary between physics and philosophy. (But unlike some more purely philosophical interpretations, it does have some mathematical meat to it.)

https://en.wikipedia.org/wiki/Quantum_logic

https://plato.stanford.edu/entries/qt-quantlog/

https://iep.utm.edu/qu-logic/

Re: The metaphysical presuppositions of formal logic

#92
post #7

IMO This article is a mess. Starts with an interesting premise, the foundations of logic (or rather, what people are taught as the foundations of logic) introduces unspoken assumptions. Then it goes on to illustrate with the worst example I can think off. modern physics’ mathematical representations [...] tend to insinuate an eternalist rather than presentist conception of time. I don't know which modern physicists h…

"Eternalism" refers to the static "block universe" conception of spacetime, where all events exist simultaneously, past, present and future. "Presentists", by contrast, hold that the past no longer exists, the future does not yet exist and only the present moment exists. Neither are positions about whether there is/was a first moment of time. I just finished reading the physicist Sean Carroll's book "From Eternity to…

> "Concerning the debate between eternalism and presentism, a typical physicist would say: 'who cares?'"

Don't some hypotheses in cosmology effectively presume eternalism? For example, the Hartle-Hawking state aka "no boundary proposal"?

Re: The metaphysical presuppositions of formal logic

#93

Earlier quoted context omitted.

Perhaps you’re right and I was overly harsh or critical of him personally. All I am trying to say, crudely put, is that it seems to me that the author has started from his prior positions and then constructed an argument that reinforces them. That’s fine by me (if he is honest about it), but I hope you can see it is hard to stomach if you don’t agree or can’t see the proof of those prior positions. Specious = “…plaus…

You're casting more vague aspersions. > the author has started from his prior positions and then constructed an argument that reinforces them There are two ways to interpret this: 1. You're accusing the author of making an argument that is circular. If so, describe the argument, including its premises and conclusion, and specify which premise is the conclusion. 2. You're merely attacking the author for arguing their…

So is Thomism(/forms of Neo-Thomism) the be-all-and-end-all of philosophical enquiry then? If an argument is based on unexamined prior positions how can it be considered sound? (I suppose there is a problem of infinite regress here/some form of ‘Russell’s teapot’ or something! :) Thomas Aquinas was/is an extremely influential and interesting thinker (especially for his time!), but I find that sadly I don’t necessarily see proof of/share his revelatory faith in the existence of a traditional Catholic God. When I try and boil down various arguments into comment form I cannot definitively argue against those ideas because, for all I know, they may be true, at least on some level... The problem is rather that, as I understand him at least, I see that equally they may not be true and that they derive in part from hefty presuppositions about the existence of god, denial of possible kinds of physical/metaphysical infinite regression (not sure I’m using that term entirely correctly, but what the hey…) /infinite universes/multiverses/even voidist/illusory universes, various other theisms (pantheism, panpsychism or ‘idealism’ for example), atheism and probably a lot more -isms that I can’t think of right now or am just not aware of… If your argument is that philosophy based on formal logic is devalued somehow because it is merely relative/can only express relations between ‘things’ and not ‘things’ in themselves, well, what’s to say that the universe isn’t entirely informationally constituted/‘mathematical’ and therefore able to be defined solely relationally in some form? (not putting that very well - but along the lines of: https://en.m.wikipedia.org/wiki/Our_Mathematical_Universe ). I don’t immediately see how ordinary language is any more potentially categorical than formal logic in such a context - though the power and beauty of words/mathematics is undeniable in a human context, is it not potentially dangerous arrogance to think that we currently/could ever hope to understand God/universal meaning on any definitive, ethically actionable or universally communicable level? Doesn’t the unchallenged adoption of such concretized beliefs invite inevitable abuse and corruption when flawed humans distort them and undesirable actions arise from calcified dogmatism/extremism/literal interpretations? Here’s some Kant, for good measure: “Thinking for one's self is to seek the chief touchstone of truth in one's self (id est, in one's own reason); and the maxim, to think for one's self at all times is Enlightening. Thereto belongs not just so much, as those may imagine who take knowledge, to be enlightening; as it is rather a negative principle in the use of one's cognoscitive faculty, and he, who is very rich in knowledge, is often the least enlightened in the use of it. To exercise one's own reason, means nothing more, than, relatively to every thing which one is to suppose, to question one's self.” — from ‘What it Means to Orient One's Self in Thinking’ ((& Monty Python’s Philosophical Football Match: https://vimeo.com/84600758 )

Re: The metaphysical presuppositions of formal logic

#94

Earlier quoted context omitted.

Is it wrong to be opinionated? Feser quickly remarks on a problem of math: some mathematical constructs reflect the system of math more than reality. If your philosophy never touches the political, the reality, aren’t you merely creating a system of reasoning for its own sake? Moreover, does he need to challenge his own presuppositions? We can do that!

I think that sometimes being overly opinionated and incapable of changing your mind is potentially harmful to others, yes… Is it not potentially dangerous to advocate for various political realities based solely on unexamined/individual opinion-based constructs? Maybe I am wrong, though… I’m curious what you think of the ideas in this article?: https://aphilosopher.drmcl.com/2007/08/26/is-philosophy-just...

I understand caution when stating opinions - it is a good instinct, but I'm not sure what you're arguing.

> I think that sometimes being overly opinionated and incapable of changing your mind is potentially harmful to others, yes… Is it not potentially dangerous to advocate for various political realities based solely on unexamined/individual opinion-based constructs?

How can I disagree with this? Yes there is hazard in advocating for anything. Moreover, there is hazard in doing anything. But I see what you're getting at. There is some line we draw in our own minds between philosophy, that is the pursuit of truth, and political - the realm of opinions.

Where is the line? Most would say that it is when the philosopher argues in good or bad faith. Thus, we are in the realm of the unknowable, the motivations of all around us. Also, not to comment on the notions of whether it's possible for an individual's to be "good" or "bad", but I don't want to digress.

To return, I think you're saying that making statements result in harm to individuals is bad. I agree, but this is a political question, not a philosophical one. Thus providing a philosophical justification or contradiction for your statement is moot.

Re: The metaphysical presuppositions of formal logic

#95

Earlier quoted context omitted.

I think that sometimes being overly opinionated and incapable of changing your mind is potentially harmful to others, yes… Is it not potentially dangerous to advocate for various political realities based solely on unexamined/individual opinion-based constructs? Maybe I am wrong, though… I’m curious what you think of the ideas in this article?: https://aphilosopher.drmcl.com/2007/08/26/is-philosophy-just...

…and yes I think that challenging one’s suppositions ought to be the first task of any aspiring philosopher. Isn’t that the whole idea?

But where does it end? Is all reason not based on a set of axioms? You can comment on your presuppositions, if you throw them all out then there is no (classical) logic.

Philosophy is a conversation, and valid argumentation is that starting point of any treatise. The work of contending philosophers is to challenge one another, so there should be no hesitation in using less-than-certain (that is to say, all) presuppositions.

Moreover, Feser does comment on his presuppositions in this very article.

> I would qualify this by saying that metaphysics is prior to logic if “logic” is understood in sense (b) described above, though not if understood in sense (a). Naturally, we have to presuppose certain canons of reasoning when reasoning about anything, including metaphysics. But it doesn’t follow that we have to presuppose the codification enshrined in some particular formal system – such as, for example, modern propositional and predicate logic rather than traditional Aristotelian logic, or rather than some system that tries to capture the best of both worlds (such as that of Fred Sommers).

Re: The metaphysical presuppositions of formal logic

#96

Earlier quoted context omitted.

You're casting more vague aspersions. > the author has started from his prior positions and then constructed an argument that reinforces them There are two ways to interpret this: 1. You're accusing the author of making an argument that is circular. If so, describe the argument, including its premises and conclusion, and specify which premise is the conclusion. 2. You're merely attacking the author for arguing their…

So is Thomism(/forms of Neo-Thomism) the be-all-and-end-all of philosophical enquiry then? If an argument is based on unexamined prior positions how can it be considered sound? (I suppose there is a problem of infinite regress here/some form of ‘Russell’s teapot’ or something! :) Thomas Aquinas was/is an extremely influential and interesting thinker (especially for his time!), but I find that sadly I don’t necessaril…

Why don't you stop soapboxing and address the comment you're replying to?

Re: The metaphysical presuppositions of formal logic

#97
post #32
post #4

Earlier quoted context omitted.

The designer is not assumed. I am it. I design formal systems. Formal systems are human inventions. Any expression or description of the “laws of thought” are subject to the limits of self-expression and the expressive power of your formal language. The “laws of thought” are rules of thumb. Useful Heuristics - not universal authorities. I recommend Luciano Floridi’s recent work in “The Logic of information: Philosoph…

Does the universe have a designer then? It’s a pretty bold metaphysical assumption that the universe is undesigned and purposeless, but it somehow gave rise to an environment where intelligent beings can design formal systems that accurately describe the design of a system with no designer. This is part of the appeal of the simulationist philosophy, it allows intelligent design, but without the assumptions of monothe…

None of our formal systems “accurately describe the design”. They all have domains of applicability - operational parameters.

The appeal of the simulation hypothesis is that IF our formalisms could actually explain all of reality THEN it follows by logical implication that reality can be simulated.

This logical implication is true because formal languages are Turing-recognizable. You can “explain” a formalism to a computer. You can program the computer with the Theory of Everything therefore universe can be run on a computer.

This is ALL in the abstract. Unfortunately humans have the propensity to commit the mind-projection fallacy.

Re: The metaphysical presuppositions of formal logic

#98
post #48

Earlier quoted context omitted.

You are talking about a different function. The function I am talking about doesn't take any arguments. [1] pry(main)> Time.now(1) ArgumentError: wrong number of arguments (given 1, expected 0)

> The function I am talking about doesn't take any arguments. All impure functions have an implicit dependency on (some subset of) the state of the universe when they execute; in mathematics and logic something with this kind of dependency is typically noted by parameterizing it by time when the actual precise nature of the dependency is outside of the scope of the immediate analysis (because a dependency on the stat…

Well, it seems our disagreeme is obvious.

You only want to talk about pure functions. I want to talk about ALL functions.

So lets define the function "pure" such that

  pure(f) -> True when f is a pure function
  pure(g) -> False when g is an impure function
What would you say is the truth-value of pure(pure) ?

https://en.wikipedia.org/wiki/Impredicativity

Re: The metaphysical presuppositions of formal logic

#99

Earlier quoted context omitted.

I think that sometimes being overly opinionated and incapable of changing your mind is potentially harmful to others, yes… Is it not potentially dangerous to advocate for various political realities based solely on unexamined/individual opinion-based constructs? Maybe I am wrong, though… I’m curious what you think of the ideas in this article?: https://aphilosopher.drmcl.com/2007/08/26/is-philosophy-just...

I understand caution when stating opinions - it is a good instinct, but I'm not sure what you're arguing. > I think that sometimes being overly opinionated and incapable of changing your mind is potentially harmful to others, yes… Is it not potentially dangerous to advocate for various political realities based solely on unexamined /individual opinion-based constructs? How can I disagree with this? Yes there is hazar…

Is it a good-faith, or bad-faith argument to point out that philosophers (myself included) don't know what they are talking about?

As in literally asking the question: What is Philosophy about?

The only answer we can give is political.

Re: The metaphysical presuppositions of formal logic

#100

This seems too vague to me, like a lot of philosophical posts out there. > For example, if it is true that Aunt May believes that Spider-Man fights crime, then even though Spider-Man = Peter Parker, it does not follow that Aunt May believes that Peter Parker fights crime. If you can't substitute Peter Parker for Spider-Man, then they are by definition not equal...

>If you can't substitute Peter Parker for Spider-Man, then they are by definition not equal...

This is too reductionist.

Can you substitute Peter Parker(before the lab accident) for Spider-Man ?

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