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I realize there's a (stereotypical) tendency for scientists and engineers to look down on philosophy - and I think this tendency colors this whole discussion to the extent that it almost borders on being a touchy subject.

But a lot of the claims about the uselessness of philosophy in the modern world are probably based around the fact that, at least from the perspective of an Ancient Greek like Aristotle, there was no actual distinction between "science" and "philosophy". It was all just sophia (wisdom) to him. It was applying abstract inductive reasoning to arrive at universal truths.

And this is patently obvious from simply reading Aristotle or the Pre-Socratics. These writers routinely make what modern readers would consider outright scientific claims. A lot of what Aristotle wrote is testable and falsifiable, and has indeed been falsified. But to Aristotle there wasn't any inherent epistemological difference between reasoning about physics and reasoning about justice. But today, we clearly separate these two spheres via empiricism - a method of thinking that wasn't really available to the Ancient Greeks, because it wouldn't be truly appreciated as part of a formal, scientific method, until the Medieval Arabs and later the European Renaissance thinkers really formalized it.

So in that sense, it's understandable why some modern students might find reading Aristotle as silly as reading, say, a Medieval book about medicine or alchemy.

I would argue, however, that Aristotle (and many of the ancient philosophers) are actually very valuable to read precisely because of their historical impact, and how their works shaped the course of human thought for millennia. Aristotle's particular ideas about physics might be hopelessly wrong, but his thought processes and writings influenced Europe and the Middle East throughout the Middle Ages and beyond. It is therefore critically important to have a good understanding of Ancient Greek philosophy if you are to have any hope of understanding the history of Western thought in general.




I'd say you're overstating the extent to which Aristotle was "hopelessly wrong" in his physical theories. It's more that the things he was right about have become so deeply ingrained in us that we don't even consider them questions of physics — they're just "how things are".

For example, his breaking down of the 4 types of causes: what a thing is made out of (material), what makes it what it is (formal), what process or force made it that way (efficient), and its purpose (final). What we today mean by "cause" usually only includes the efficient cause, so calling the rest "causes" can confuse more than it illuminates (at least at first). But everyone of course understands how to analyze things in terms of their matter, form, and purpose, even though we don't call them "causes" and we don't consider it "physics."


With Aristotle in particular, I was thinking mostly of his statements about gravity and objects moving towards their natural place.


This is an interesting take on how Aristotle's physics was more correct than he is usually given credit for:

https://arxiv.org/abs/1312.4057


The point is that yes, there are some things he was wrong about, and when we think of the questions that "physics" amswers, those are the ones that come to mind. But that ignores the contributions he made that we don't think of as contributions at all because we take them so for granted that it's not at all clear to us that people could ever have thought otherwise. I don't know if the aitiai are the greatest examples of this, but the entire approach of questioning why objects move and change the way they do and trying to reduce it to a concise set of rules? My understanding of history is that that was very novel.


I agree. I don't downplay Aristotle's massive contribution to the development of human knowledge. I just claim it is more of historical significance than practical significance. I mean, Aristotelian physics has no real technological applications in the same way that Newtonian physics is used by rocket scientists or Einsteinian physics is used by your GPS.


Absolutely! I was actually thinking of the change and movement stuff too but I couldn't think of a concise way to express it like you can with the causes.


How far of Lagrangian mechanics this is ?


Most philosophers will readily acknowledge the pitfalls of early philosophy - many pre-Socratic views are indeed falsifiable, and Aristotle makes all kinds of silly physical qualifications surrounding virtue and its prerequisites.

The view that empiricism is what divides science and philosophy is a controversial one. Many philosophers and students of philosophy (including myself) think that there exist empirical truths in the fields of ethics and metaphysics, the latter of which is not scientifically testable by definition.

I like to distinguish science and philosophy in terms of their object of study - the sciences inform our knowledge of the external world, while philosophy informs our knowledge of ourselves and (the rightness of/the reasons for) our behavior within that world. I don't think that's a perfect definition, but it comes close to explaining the need for empiricism in both fields.


What do you mean by empiricism? I was always under the impression that observation and experiment are what empiricism is all about so I don't understand what you mean by saying that it is empirical but not testable.


Philosophy engages in observation and experiment just like the sciences do. It's just that those observations and experiments tend to (but don't always!) run orthogonal to scientific ones.

You can test metaphysical claims via a metaphysical framework or even "pure logic" (according to some), just not via normative physics. For example, how can physics even begin to prove that you or I exist? It can qualify our existence as objects in a world, but this says nothing about our minds, their "location", why they exist, why they're different "things" (if they are different things), and so forth.

Edit: To the downvoter, please respond as well. Silence hurts more than disagreement.


I did not downvote you (I have no time for people who downvote without explanation), but I do think that philosophical 'experiments' are not at all like science experiments, and the salient difference is precisely the lack of an empirical arbiter. Your second paragraph is a good argument for that point.

One consequence is that philosophical experiments rarely reach a conclusion (except when science does catch up, as will probably happen over consciousness, for example.) I have come to realize that reaching a conclusion is not the point; the discussion is the point.


I think the point of the empirical arbiter is an interesting one. My second paragraph can indeed be used as an argument for the absence of one in philosophy.

But where is such an arbiter in science? After all, science is inductive, not deductive. It can give you lots of good reasons and evidence to believe a theory, but the principle of falsifiability requires that a counterexample must plausibly exist.

If either philosophical or scientific experiments were to reach an unfalsifiable conclusion, I think we would have a serious problem on our hands.


Can you give any examples of philosophical ideas proved experimentally?


Proof theory itself. You can thank Boole, Cantor, Peirce, Russel, Frege, and Peano (among many others) for that.

Depending upon what you mean by a proof, there are also "ideas" in philosophy that are trivially true:

1. I am.

2. There is a thing that I am.

3. The thing that I am is me.

4. I am me.

These are completely trivial, but they're also interesting from a language-and-object perspective.


I'd expect philosophy to try and dive into what point 1 actually means rather than to jump to conclusions with points 2 to 4, otherwise it becomes mostly a practice of defining axioms within the realm of thought and manipulating concepts and relations, much like mathematics but without the practicality (in most cases). Of course, answering what point 1 means could require venturing beyond the scope of what can be reached by thought alone, which would place it outside the acceptable scientific boundary. It appears to me as if philosophy is in the unfortunate position where on one hand, it is ill equipped to answer the deepest questions and on the other it can't arrive at any important and empirically falsifiable conclusions.

Would be happy to be proved wrong, though.


Oh, they were meant to be individual axioms, not a cohesive argument. That's what makes them interesting - they're four things that say essentially the same thing, but with profoundly different implications and preconditions.

> otherwise it becomes mostly a practice of defining axioms within the realm of thought and manipulating concepts and relations, much like mathematics but without the practicality (in most cases)

That tradition in mathematics comes from analytic philosophy. That's not to say that all philosophy is about defining and manipulating relations (it isn't, and shouldn't be), but that language-games (to borrow Wittgenstein's term) are a subject of valid inquiry.

> It appears to me as if philosophy is in the unfortunate position where on one hand, it is ill equipped to answer the deepest questions and on the other it can't arrive at any important and empirically falsifiable conclusions.

Yeah, it often appears that way. However, we except such a sorry state of affairs in theoretical physics and the workings of the mind -- why should we be any less charitable with philosophy?

> Would be happy to be proved wrong, though.

With emphasis added: wouldn't we all? ;)


> However, we except such a sorry state of affairs in theoretical physics and the workings of the mind -- why should we be any less charitable with philosophy?

Well, personally I don't expect nor accept any non-falsifiable theories from any branch of science. There is a tendency to relax this requirement in some theoretical fields of physics and to say that it suffices if a theory is empirical and unambiguous. Of course one can make the line fuzzy with some of them and say that they are tentatively falsifiable (i.e they can be once humanity will be reach a certain level of progress), but as far as I'm concerned, those type of theories are more suitable as a special branch of mathematics than of physics. Perhaps philosophy can help in categorising these theories ;)

>> Would be happy to be proved wrong, though.

>With emphasis added: wouldn't we all? ;)

Yes, well, I never claimed to be free from the constraints of thought :)


Why would you file proof theory under philosophy as opposed to mathematical logic? Proof theory isn't any less mathematical than, say, the integers. You start with a fully formal set of ground rules specifying the system you're studying, and then use a specified mechanism of formal deduction to determine features of that system that are a product of that specification.

You can use proof theory to strengthen/weaken claims in the philosophy of mathematics, like how Godel's incompleteness theorems removed the possibility of a universal logical framework for all possible mathematics. But you're doing the same when you shoot down Aristotle's claims with the physical sciences, so I don't see why you would that would be a reason to file it under philosophy.


If you are going to exclude anything that could be considered mathematics or science from the domain of philosophy, then trivially, you will find that philosophy concerns things which can't be precisely quantified or empirically proven.

Proof theory does, however, originate from the work of philosophers (Aristotle being a salient example), and issues relating to proof theory are central to epistemology and metaphysics.

One problem that philosophy has is that its most conspicuously successful branches often become disciplines in their own right, so that philosophy doesn't get any credit.


There's a difference between excluding them from the domain of philosophy, and co-opting them as developments of philosophy. The distinction here is that the methods used to develop proof theory look exceedingly similar to how mathematics is developed, and quite alien to the methods of philosophy both of that time and now. Frege didn't develop his proof theory by spending years doing literary reviews of previous philosophers, or by writing papers and books based on suppositions.

You're right that proof theory, like mathematics and science, branched off from philosophy some time in the past. But looking at the successes of these branches as evidence that you should read old philosophy or engage in the mainstream methods of contemporary philosophy when their methods are worlds apart does not make much sense.


>The distinction here is that the methods used to develop proof theory look exceedingly similar to how mathematics is developed, and quite alien to the methods of philosophy both of that time and now.

Logical reasoning has always been one of the methods of philosophy. It seems quite bizarre to say that the development of proof theory has nothing to do with philosophy, which for millennia prior had been interested in the question of what distinguishes good arguments from bad arguments and which arguments are formally valid.

Also, proof theory does not look that much like the rest of math. It certainly doesn't look much like the math that people were doing in Frege's time. So I don't really buy the argument that proof theory is distinctively "mathematical" as opposed to "philosophical" (to the extent that these terms are meaningful in the first place).

>Frege didn't develop his proof theory by spending years doing literary reviews of previous philosophers,

I'm not exactly sure what "doing literary reviews" is supposed to refer to, or why you think that this is more characteristic of philosophy than logical argumentation, but Frege certainly read previous philosophers. To a significant extent Frege's work is a reaction to the limitations of Aristotelean logic. And it's pretty clear from reading Aristotle that he didn't think of the study of logic as a branch of mathematics.

>But looking at the successes of these branches as evidence that you should read old philosophy or engage in the mainstream methods of contemporary philosophy when their methods are worlds apart does not make much sense.

Could you elaborate? I'm not sure which methods you're referring to.


> Logical reasoning has always been one of the methods of philosophy. It seems quite bizarre to say that the development of proof theory has nothing to do with philosophy, which for millennia prior had been interested in the question of what distinguishes good arguments from bad arguments and which arguments are formally valid.

Logical reasoning in the form it takes in the philosophical works of any of the philosophers you mentioned and the kind done in mathematics are worlds apart. Comparing Spinoza's "proofs" which are supposed to follow the style of geometric proofs with actual geometric proofs reveals a pretty stark contrast. More generally, philosophers rarely phrase their logic in a formal language (although they do on occasion), while mathematics has been done only in a formal logic since the advent of proper axiomatic foundations in the early 20th century. Informal reasoning is often used to assist formal arguments at an intuitive level, but no mathematician takes it seriously on its own.

How many philosophical works do you see start with a list of fully precise axioms and then continue only use those as assumptions, making their uses clear? There are a few I can think of, but they are far from the norm.

> Also, proof theory does not look that much like the rest of math.

How so? Even early results like Godel's incompleteness theorems look strikingly like other mathematical proofs. He lays out the precise definition of a formal system, and even sets up an encoding for sentences of that language in the natural numbers. A significant part of it is also pretty much straight out of Cantor's diagonal argument.

More modern proof theory looks even more like conventional mathematics, with a lot of it being phrased in the language of category theory.

> And it's pretty clear from reading Aristotle that he didn't think of the study of logic as a branch of mathematics.

Yes, because the mathematics of Aristotle's time was not equipped to handle something like proof theory. Frege (as well as the others you listed) at the very least thought the right way to study logic was through mathematics.

> Could you elaborate? I'm not sure which methods you're referring to.

Okay, pick 10 papers at random from a philosophy journal of your choice. How many of them are yet another examination of the one of the works of "old philosophy" the original article was imploring us to read, and how many are exploring something new? I don't mean "something new" as in standing completely alone and without any references to past works (I've yet to see such a paper in math or science), but simply drawing conclusions that are something other than a response to an age old argument. And as I said before, how many use formal logic as opposed to informal logic?


>More generally, philosophers rarely phrase their logic in a formal language (although they do on occasion), while mathematics has been done only in a formal logic since the advent of proper axiomatic foundations in the early 20th century.

I don't see any distinction between the two disciplines here. Philosophers make use of formal logic when it makes sense to do so (lots of discussion of the ontological argument makes uses of formal logic, for example [1]). Mathematicians follow exactly the same strategy. It's quite false to say that mathematics is now done only in a formal logic. The vast majority of mathematical proofs are presented informally (even in textbooks on logic!)

>How so? Even early results like Godel's incompleteness theorems look strikingly like other mathematical proofs.

I guess the best example is Frege, whose work was ignored by mathematicians and logicians alike because it looked completely alien. But I was thinking more of, say, proofs of completeness for systems of propositional logic, which are highly notation-dependent and consist in running through a bunch of cases in a boring mechanical way. Peirce and Gauss seem worlds apart.

> Frege (as well as the others you listed) at the very least thought the right way to study logic was through mathematics.

I'd say he thought that the right way to study mathematics was through logic. In other words, he was trying to put mathematics on proper logical foundations. (This is the project that Russell tried, and essentially failed, to complete.)

>how many are exploring something new? I don't mean "something new" as in standing completely alone and without any references to past works (I've yet to see such a paper in math or science), but simply drawing conclusions that are something other than a response to an age old argument. And as I said before, how many use formal logic as opposed to informal logic?

Most conclusions in philosophy are responses to age old arguments for the very simple and obvious reason that people have been thinking about philosophical problems for a long time. Occasionally people do come up with new problems, of course. The philosophy of language would be one example where lots of genuinely new questions have arisen and been given interesting answers (partly as a result of developments in mathematical logic).

It's quite common for philosophy papers to use formal logic, but only when it is helpful. In exactly the same way, mathematical proofs are presented formally on occasion, when it is helpful, but not as a matter of course.

[1] https://philpapers.org/archive/OPPOTL.pdf


These are not trivial at all. Read Metzinger's "The Ego Tunnel" for more information. There are neural nets within neural nets, but there is no such thing as "me", "you" or "I". Also additionally Dawkins's "The Magic of Reality" is quite a food for thought.


Look at something like archaeology. You can find an artifact in a garbage pit and record it as an observation. Few would challenge this activity as unempirical. On the other hand, no experiment will be able to reproduce your find: once you've dug it up, you've dug it up. The best you can hope for is to find something similar at another site.


I think the poster may be thinking of the kinds of statements that Kripke argued were necessary truths that could only be known a posteriori.


I have Naming and Necessity on my bookshelf ;)


>that there exist empirical truths in the fields of ethics and metaphysics, the latter of which is not scientifically testable by definition.

This is a digression off the main subject, but at least with respect to ethics I think that's a pretty bold claim. Ethical naturalism is a perfectly mainstream school of thought, and they don't share this definition of ethics.


> sciences inform our knowledge of the external world, while philosophy informs our knowledge of ourselves and (the rightness of/the reasons for) our behavior within that world

How would you categorize ethology, behavioral neuroscience etc?


Not sure I can get behind this. We read primary sources in history, but in those cases it is to get understanding that can only come from a first person account, like subjective experience. With philosophy, it is argued that Aristotle's thoughts can only be fully conveyed BY Aristotle (aside from the hero worship of some philosophers I know).

My sense is that you're really on to something with empiricism. Philosophy is now largely about purely social phenomena, like epistemology and ethics, that don't have a physical "correct" answer (at least to most people--maybe not Kant). That being the case, there really is something unique about, for example, Aristotle's take on virtue ethics, since there is no virtue ethics outside of his conception of it (and our practicing of it). So the pure thing being studied in philosophy is Aristotle's conception and the surrounding literature of virtue ethics, whereas with physics and Newton his theories and equations are pure things and there is no value to his particular exposition.


Ancient Greek is stained by history - it was the only science taught in Universities for what? a thousand years. That's the catch - its revered beyond all reason due to history. Simultaneously its old-fashioned and outdated for the same reason. Hard to disentangle the two.

I read the Philosophers in College. But I cannot imagine I would ever again pick up a book of Ancient Greek Philosophy. There's just nowhere to go from that stuff. Informative as history, and as an intro to the subject. But I been there; done that.


>There's just nowhere to go from that stuff.

Many of the questions Aristotle was grappling with are still open questions. E.g., are there essences? Do statements about the future have a truth value? What is the good life? What is causation?


>Ancient Greek is stained by history - it was the only science taught in Universities for what? a thousand years. That's the catch - its revered beyond all reason due to history.

That's reversing cause and effect. It's not a mere accident of history that it was "taught in Universities for a thousand years".

>But I cannot imagine I would ever again pick up a book of Ancient Greek Philosophy. There's just nowhere to go from that stuff

Actually it's one of the best investments in one's personal development and understanding of the world they could make.

Physical philosophy aside, philosophy, like arts, doesn't get deprecated over time. Aristotle, Plato, Seneca, Epictetus, Leibniz, Spinoza, Kant, etc are as relevant as they ever were.


Sure it was. It was all they had for 'science' for a thousand years. Something about the 'dark ages'.

And, as stated above, been there and done that.


>Sure it was. It was all they had for 'science' for a thousand years. Something about the 'dark ages'

There was not much "dark" about the dark ages (as 20th and 21st century scholarly research increasingly showed), and what little was was due to the collapse of a huge organized empire, not because because "that was all they had for science" (I guess "that" being Aristotle).

In any case, this is an extremely shallow assessment of the role of philosophy -- like someone reading Cliff Notes on Shakespeare and thinking they got all there is to it.


> It's not a mere accident of history that it was "taught in Universities for a thousand years".

What are your reasons for this that are not historically contingent?

> Physical philosophy aside, philosophy, like arts, doesn't get deprecated over time. Aristotle, Plato, Seneca, Epictetus, Leibniz, Spinoza, Kant, etc are as relevant as they ever were.

Except Kant and Leibniz believed things about mathematics and logic that were later found to be unequivocally false. Plato's view of mathematics is still arguable if you rephrase it enough, but it needs some big modifications. Spinoza's attempts at writing his arguments as if they were geometrical proofs are a joke, he pulls axioms and rules of deduction out of the air.

That's not to say that the things they said about the non-physical (even the ones already found to be wrong) are not valuable, but they're a far cry from being "as relevant as they ever were."


That's funny, I've seen Stoicism making inroads in various places lately, including this very hallowed forum.


Because when people hear "ancient Greek philosopher" they think of Socrates, Plato, and Aristotle. Figures like Zeno and Epicurus are mostly overlooked.


You could also history is stained by the ancient Greeks--and thus the present is stained by ancient Greek thinking, which is exactly why it's so important to study. Aspects of morality or the scientific method that we take for granted need to be understood in a historical context, and if you want to understand the modern world, you need to understand the thousand-year foundation it's built on.


My criticism of philosophy nowadays is not that it isn't valuable to read, but that it's not read from a historical perspective. Instead, people to often read i.e. Aristotle as if it contains modern truths. While some parts of Aristotle remain true, his ideas have been greatly refined over centuries, and integrated into our culture to the point that uneducated people in the modern world often have a stronger grasp of practical philosophy than Aristotle did.

But too often old philosophy is taught and read in a vacuum, not as history but as a source of practical modern philosophy. This results in repeated resurgences of bad ideas that were refined away by more modern advancements in philosophy, but are revived when people read old philosophy uncritically. Few people have an understanding of the refinements to even refute many older philosophers claims.

Moreover, there are many accepted ideas which we take for granted that should be more deeply questioned which come from philosophy. For example, the pervasive Socratic idea that mind and body are separate entities is all but disproven by modern understanding of the nervous system, but it's deeply ingrained in our culture, and needs less reinforcement, not more.


> I would argue, however, that Aristotle (and many of the ancient philosophers) are actually very valuable to read precisely because of their historical impact, and how their works shaped the course of human thought for millennia.

You could make the same argument for theology, yet you rarely hear people talk about the importance of reading someone like Irenaeus (for example). And if someone like that is studied, it's often looking at their historical context and their historical impact, rather than someone like Aristotle where the focus is often on the works itself. You don't see many people saying we should be reading and arguing Irenaeus' theological theories.

A class on Aristotelian epistemology is not a class on "Western thought," and trying to mask the former by disguising it as the later only suggests that there isn't a terribly great reason to study it.


I wouldn't equate Aristotelian epistemology to "Western Thought", but I could surely imagine a course on the history of western thought that took Aristotle's treatment of epistemology (or whatever else) as an important landmark.


Sure. I once took a course on modern Iranian history that had us read Khomeini's "Islamic Government." But that's very different from how the book would be studied in an Iranian seminary. A historical look is interested in how something ties into the surrounding history, and doesn't pass judgement on the quality of the writing or spend time trying to determine its soundness.


It sounds like we agree more than we disagree. I would substitute a term like "ties into" for "influenced/gave rise to/made possible."

We don't really need to know much about the merits of any particular Aristotelian investigation these days. But that material can be critical for helping us understand, and yes, helping us critically evaluate, the schools of thought it gave rise to.


It's interesting that even within the field of philosophy the term sophist/sophistry from the root sophia has come to denote deception and fallacy rather than knowledge or wisdom.

I would agree that philosophy has evolved somewhat (Nozick and Rawls), but for me it never really achieved the level of empirical usefulness (past perhaps rule utilitarianism), because it has never been clear enough how (or even when it was appropriate) to apply it. If there were such a thing as "Newtonian" philosophy that had useful testable equations, perhaps I would view it differently.

At least I have some idea when physics rules break down and when they are useful approximations. In my experience most philosophy is written as if it is completely true not a model of reality.


In Greek you can use the same root for different purposes. I.e. it is not the word sophia or sophos that came to denote deception or fallacy. Sophist is someone who deceives using the pretense of philosophy.

I do not see knowledge as something that comes with an application manual. I.e. there is no manual defining how will use number theory, but still it has applications, sometimes completely unexpected.

I would argue that philosophy navigates the fields where the testability of equations and "hard" science fails. That is also why some scientists do philosophy when/where the rules break down.


>wouldn't be truly appreciated as part of a formal, scientific method... until... [later] thinkers really formalized it.

They didn't formalize empiricism or the scientific method. They couldn't have because they didn't have the tools. In fact, it's still not formal.

The reason nobody formalized the scientific method is that science depends entirely on the process of induction, and nobody understood induction in any kind of formal, rigorous, mathematical way until the middle part of the 20th century, with the work of men like Kolmogorov, Solomonoff, Vapnik, and Chaitin.


Aristotle had historical impact, but there are ancient philosophers whose ideas were much more useful. In particular, I would point to Zeno (of the Stoics), Epicurus, Democritus, and most of all, the Buddha.




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