Nagel Asks, Is the World Really Knowable?
"Can we actually 'know' the universe? My God, it's hard enough finding your way around in Chinatown." -- Woody Allen
Thomas Nagel's important Mind and Cosmos: Why the Materialist Neo-Darwinian Conception of Nature Is Almost Certainly False has already received some attention on ENV -- regarding his respectful comments on intelligent design in particular. What's the rest of it about?
Nagel's is a book ultimately about whether the world, and all in it, is completely knowable, at least in principle. According to the author, a distinguished philosopher at NYU and an atheist, it isn't. See, the world is filled not only with objects, like rocks and trees, but also with subjective first person viewpoints: yours, mine, and those of other conscious creatures. Yet our favorite third person way of knowing, science, was not developed to get its arms all the way around these oddities of existence, says Nagel. Science does objects well, that is. Subjects? Not so much.
Since the all-is-knowable crowd -- alternately addressed by Nagel as reductionist on mind, naturalist on epistemology, materialist on metaphysics and Neo-Darwinian on biology -- pins its hope for complete knowledge on science, the book is also about the inherent limits of science-as-applied-materialism, and how those limits might be overcome by ditching materialism for some form of teleology.
On those limits, science is, at least, a set of tools and ideas useful to innovators and engineers for solving problems of a physical nature, like how to build a better mousetrap, or useful for science teachers to initiate science students into science practice. To say that that's all science is good for -- technology or pedagogy -- is to embrace scientific instrumentalism. Nagel doesn't do that. At most science can also accurately describe physical reality, even (and most importantly!) the stuff we don't see. Take, for example, the idea that invisible electrons are not merely useful social constructs but real entities, real things whizzing about atomic nuclei. This is an instance of scientific realism. Nagel charitably grants scientific realism to the materialist.
If, however, the world contains not only particles in motion, concededly fully describable by science, but also includes subjective first person viewpoints that are not reducible to particles in motion (i.e., the brain state over which a mental state arises are not identical to one another), and thus at least partly inscrutable to science, then science even at its best could never offer a complete picture of the world. That is, science as science will necessarily lack the vocabulary to capture and express the myriad private worlds of subjective, conscious experience. To take Nagel's famous example, science could tell you everything you want to know about bats except what it is like to be a bat, to "see" via echolocation. Similarly, brain scientists could in principle learn every objective fact about your brain and how it works yet they wouldn't by virtue of this knowledge know what sugar tastes like to you.
In the final chapter of the book, Nagel sums the matter up this way:
[I]n attempting to understand consciousness as a biological phenomenon, it is too easy to forget how radical is the difference between the subjective and the objective, and to fall into the error of thinking about the mental in terms taken from our ideas of physical events and processes.Mind and Cosmos serves firstly as a reminder that there are some things that science can't do, can't say, and that as a result all is not knowable. And unless you're in the science-unveils-all business, as some seem to be, a little mystery in the world is not such a bad thing.