I just recently ran across the following quote, from a physicist I respect greatly (and no, it's not Richard Feynman): "Maybe physicists would complain less that philosophy is useless if it wasn’t useless." The original post is here (this quote is the very last sentence of the post).
Dr. Hossenfelder is hardly the first physicist to say such a thing, and I think it's pretty clear that the above quote is for rhetorical effect since one of the very first things she says in the post is that "...I think it’s an unfortunate situation because physicists ... could [use] help from philosophers."
Right away then, it seems like two things are being conflated in that first quote. On the one hand, Dr. Hossenfelder is claiming that what current philosophers produce is useless, but on the other hand she seems to accept that philosophy as a field has value and could potentially contribute to questions faced by scientists (namely, theoretical physicists).
[She does, later in the post, say some things about how philosophy only applies to 'pre-science' and is useful only when it develops such an area to the point where it becomes useless. I think that's not quite right, but I'll leave it for another day.]
So, if philosophy is---in principle---useful, but as now practiced useless, the question that naturally arises is 'how do we get from here to there?' That is, how should philosophers (of science mainly---I'm presuming Hossenfelder has no truck with ethicists and logicians) do philosophy so that it isn't useless?
I'm a philosopher, not a scientist, so I have no special authority to answer this question. I would welcome suggestions from practicing scientists! What I will do (in typically philosophical fashion) is respond with my own question: "Useful for what?" And here is where I'm going to do that thing physicists supposedly hate---split semantic hairs.
To say that philosophy is useless without telling me what it's useless for is unhelpful. Philosophy is useless for mopping floors or making an omelette. It might also be useless for devising, building, and calibrating measurement devices (I don't actually believe this, but I'm happy to grant this for the time being).
Here are some things I think philosophy is useful for:
- Ouroboros-like, examining what inquiry (scientific and philosophical) is useful for at all.
- More specifically, articulating for ourselves and others why the project of science is valuable.
- Providing a place to actively question assumptions and received truths which are not actively questioned in scientific or everyday contexts.
- Helping to remind ourselves of how very little we know.
These four are not exhaustive of philosophy's utility, but I have a personal interest in each:
As for (1), it is an open question why we should do anything beyond living a hand-to-mouth subsistence lifestyle with the aim of reproducing. Now, I expect anyone who reads this has an answer to that question: fine. I do too. The point is, we don't all agree on what the answer is, and even to the extent what we think others are wrong, we'll probably disagree about why they're wrong as well. This conversation belongs to philosophy. You can refuse to enter into the conversation, but you can't say that the conversation is pointless or meaningless without unwittingly taking part.
As for (2), I think this question is one of the most central, deepest, and largely ignored questions of the modern world. We're exploiting our remarkable theoretical and empirical successes to do all sorts of things (build smartphones, write blogs, construct skyscrapers, cure illnesses, etc.). Is this what makes science valuable? Is it the only thing that makes science valuable? Is our *understanding* of the world important too? Does the knowledge that everything is made of innumerable tiny things which combine in complex and surprising ways make us better, or let us have better lives? And what does it mean to have a better life? Again, no doubt, many will have an answer to this question---but let's not pretend that everyone agrees, or that all but one answer is completely indefensible.
Moving on to (3), I'm reminded of a couple of experiences of my own from several years ago. I was taking a (philosophy) class about relativity (taught by the wonderful John Manchak). There were a number of physics majors in the class. At one point the question of interpreting a part of the theory came up (unfortunately I can't remember any of the details, all I can recall is that it was---I think---about positing an unobservable absolute space) and several of the physics students announced the choice was clear---by Occam's razor the simpler theory is the correct one. One of the philosophy grads in the class pointed out that Occam's razor isn't an inviolable truth, and it would require justification! The physics students were nonplussed to say the least. The point here is that while the physicist is well served in the practice of physics to accept Occam's razor, it can and should be open to examination and the question of justification! And as it turns out, evidence for the razor is perhaps not as robust as one might presume (don't get me started on the problem of induction!).
There was a second incident in the class that sticks in my mind too. We were busy working away, and dealing with some question or other (again, regrettably I forget the specifics). In examining whatever it was, a grad student (in philosophy, but trained in physics) pointed out that some answer would violate the conservation of energy, and so we could discard it. It was pointed out that the conservation of energy was not some a priori logical truth*, and there was no reason (for our purposes) to presume it was true. At this point I witnessed the closest thing to a brain short-circuiting I've ever come across. The student couldn't comprehend this possibility! Again, if scientists constantly questioned the conservation of energy then we'd never get anything done. But it does not follow from this fact that it's useless to think about the possibility that such a principle is in fact false (also, I'm not claiming no scientist ever does question such conservation principles!). This idea, that thinking about the possible falsity of our most empirically well-confirmed theories is something worth doing, leads to the fourth thing philosophy is useful for.
(4) The success of science (by which I mean, specifically, its empirical predictions) and the proliferation of its applications work to instill in us the sense of its epistemic impeccability. But the practice and history of science also pulls in the other direction (this is what Kuhn called 'the essential tension')---overturning our closest and most foundational beliefs, revealing the intelligibility-defying character of parts of the world closed off to our senses. We have a choice about whether to take science's defining feature as the body of knowledge it delivers, or as the attitude and technique which reveals the depths of how little we know and understand. Science does both. But I think it's healthy to take the latter view seriously, that one principal value of science is that it shows us that, and how, we should give up our beliefs (I'm shamelessly stealing this particular phrasing from Bas van Fraassen's Empirical Stance, but I don't have the book with me, so I can't cite the page---sorry!). Science doesn't and can't do this alone, and this isn't the sole utility of science by a long shot---I very much like my smartphone and penicillin. But thinking philosophically, asking about reasons, assumptions, possibilities; imagining alternatives and questioning received truths, these things are (I claim) useful. It's just that they're not useful for delivering knowledge---I am of the opinion that philosophy is simply not an epistemic enterprise. Instead, they're useful for helping disabuse ourselves of the seductive idea that we know it all.
Ok, well this was a longer post than I was planning. To sum things up, philosophy is useless for some things, and many of those things are things which scientists need. But philosophy is useful for other things, and these too (I think) are needed by science, even if practitioners don't agree.
Will philosophy answer whether reality is composed of strings or a space-time lattice? No. Will it be the medium through which we can coherently ask the questions of whether our concepts are adequate for understanding such claims, or whether we need new concepts, or whether such claims are so far removed as to be meaningless or ... ? The answer to this, I think, is yes. Of course this is in part motivated by a desire for job security. But it also motivates why I want a job doing philosophy at all---I think that science is the best bet in the house, and I want to understand why.
*And yes I'm aware of Noether's theorem---it establishes it that a time translation symmetry guarantees (explains?) the conservation of energy. However, the claim that there is a time translation symmetry is on an epistemic par with the conservation of energy, and so while this theorem provides a deeper understanding of conservation laws, it doesn't prove that energy is in fact conserved.