There's a claim I laid out from Deleuze in the episode that I wanted to bring up for explicit discussion. I think it's provocative and deserves some thought but is almost certainly wrong.
It's about the picture of science as producing concepts and not propositions. I gave the example of Descartes's Cogito, and laid out a few of the apparent claims involved in that (the inference from thinking to a persistent subject doing the thinking, for one) that haven't historically stood up to criticism very well. I said there that Deleuze would point to a case like that to demonstrate that when you extract conceptual features and make them into regular old propositions, they become "mere opinions" of no scientific value, and you get endless, largely fruitless debate. This is what makes many people just dismiss philosophy as a lot of hot air.
But of course you could just take the case to be demonstrating weaknesses specific to Descartes's position. So I'd like to invite readers here to consider other cases that they have some recent familiarity with to see if the same holds up. Here's an example from the top of my mind:
Santayana in laying out artistic appreciation is trying very hard to be naturalistic and stick to observables, but isn't pedantic about it; he still talks at a high level of abstraction and doesn't spend really any time talking about his method. I can very well look at what he's doing as creating (more better, refining) concepts of beauty, apperception, matter, form, and expression. But is it the case that if you transform these into specific propositions, they just seem like ungrounded bullshit? Here's the main one: "Beauty is pleasure objectified." Assuming we've established sufficiently what that means (and if you can't get it from the topic announcement, you'll have to wait a week or two for the episode), the claims involved here are about experience and about linguistic usage: that while we don't always feel pleasure when calling something beautiful, we're saying that not just that it has the capacity or usual tendency to produce pleasure, i.e. that it is a means to produce pleasure, but that it is in itself as an end pleasurable. Now, we could proceed to debate whether that really makes sense, whether we're in making such a judgment making an ontological mistake of some sort, and then evaluate whether Santayana's account plausibly captures the experience and the semantics involved. I'm not going to actually go through the process of trying to pull out all of the component claims of Santayana's account here, but we could attempt it. In evaluating these claims, there would definitely be room for disagreement, and our counter-proposals could go back and forth indefinitely as Deleuze says. But does this mean that those propositions wouldn't accurately represent Santayana's view? That he's not making "claims" at all but merely creating some definitions? I don't find this plausible.
It may still be that the claims involved are "of no scientific value" in that the claims, while at root empirical, are not testable by means of empirical science. More work would need to be done to try to pull out some testable hypotheses from Santayana's account. I don't believe, however, that no understanding occurs prior to that point, or that doing so would be of particular additional interest. So yes, science and philosophy are often doing different things, but the way to capture this difference isn't to say that philosophy is not making claims at all, not putting forth propositions, or that if it is, they are by necessity mere opinions and so would not constitute knowledge.
I invite you all to subject your current theories to Deleuze's challenge in this way and see if you see any merit in it.