I’m paraphrasing, but not much. There seem to be at least three distinct ways scientific answers can be brought to bear on philosophical questions, with Krauss asserting the third one.
(1) Scientific data can set limits on what philosophical inquiry might reasonably assert. These cases are the easy ones. A question that seemed inherently theoretical turns out to be demonstrably amenable – on its own terms – to empirical investigation. Heideggerian speculation on how Dasein orients itself towards death is arguably a good example of this dynamic. There are now ways to measure – for instance – the degree to which preoccupation with individual finitude seeps into cognition. Those measurements don’t resolve the Heideggerian question but they do limit what you can say about it. Under this line of reasoning, there’s no difference from Heidegger commenting on Being-Toward-Death and the pre-Socratics speculating about the heavens. Neuroscientists just needed better telescopes before they could contribute.
(2) Scientific theory can set limits on what philosophical inquiry might reasonably assert. These cases are a little more tangled. There are unarticulated intersections between scientific and philosophical domains that, once properly worked out, indicate how definitive scientific results implicate tentative philosophical speculation. But homology-hopping across different architectonics is difficult enough within philosophy, where there is specialized language designed exactly for that purpose. Boundary-policing philosophers can always find distinctions that, whether ultimately tenable or not, argumentatively keep philosophy insulated from science. Nonetheless Scott Aaronson’s 53 page Why Philosophers Should Care About Computational Complexity makes a strong case for places where the tree of philosophy can be trimmed by the sheers of science.
(3) Scientific theory or data can simply answer philosophical problems. This category is the one that’s so often abused by pop science and science journalism: e.g. neuroscience explains why musical is beautiful, evolution explains why men fall out of love, genetics explains why kids turn bad, and so on. But questions of aesthetics, intersubjectivity, and morality are almost always independent of scientific results, either because they’re concerned with emergent phenomenon irreducible to science or because they hinge on stasis points that can’t be resolved by science.
Enter the increasingly noisome parlor trick of linking neuroscience to free will, where the claim is blandly made that the former demonstrates the impossibility of the latter. The argument is that neuroscience has shown the mind to be empiphenomenal, which straightforwardly implies determinism, which straightforwardly implies no free will. Of course neuroscience has shown no such thing, but that’s a different debate. The relevant mistakes here are conceptual. The first is to assume that an epiphenomenal mind would necessarily imply determinism, which it might not for reasons including the mediating role language plays in accessing the brain. The second is to assume that determinism would necessarily imply no free will, which it might not for reasons including evolutionary and neuroscientific ones. In other words, motivation might be irreducible to brain scans, and free will might not hinge on determinism. Untangling consciousness increasingly seems like a conceptual task – probably fundamentally so – which sharply reduces the odds that science might have something definitive to say.
But there are other philosophical domains where science might have more purchase, albeit not as much as some scientists would boast. Here Lawrence Krauss more or less claims to dissolve metaphysics by answering the question “why is there something rather than nothing.” The basis for his answer is derived from theoretically combining empirically-validated theories in quantum mechanics and relativity.
That’s a touch over-exuberant. What he’s actually dissolving is the Cosmological Argument, which rests either – depending on how it’s phrased – on the rhetorical question “how can there be something out of nothing” or the assertion “nothing can’t produce something.” It turns out that the rhetorical question has an answer, and that the assertion is false:
* What Can Experiments Tell Us About Heidegger’s Being-Toward-Death Speculation? [Icon Index Symbol]
* Why Philosophers Should Care About Computational Complexity [Shtetl-Optimized]
* Morality Without “Free Will” [Harris]
* Is consciousness epiphenomenal? Comment on Susan Pockett [Gomes / J Consciousness Studies]
* On Neuroscience, Free Will, Morality, and Language [Omri Ceren / Commentary Contentions]
* Freedom Evolves [Freedom Evolves]
* What Is It Like To Be A Bat? [Nagel]
* Physicist Lawrence Krauss Explains How Everything Comes from Nothing [Open Culture]