Sil, a fair amount of what you say I agree with, and is of course the basis of Decartes’ doubt. The reason why I introduced my beliefs the way I did is because I recognize, of course, that there is no reliable argument for objective truth. All I can say is what I experience, and there’s no reason why my experiences correlate with any “external world” in any sense. Fundamentally there is no way for me to show that there is such a thing as objective reality. I acknowledge all of this, and I know that philosophically that’s an important thing to acknowledge.
But once it’s acknowledged, it has to be moved past. Here’s why: if you can’t shrug your shoulders and say “I can’t prove it, but I’ve got to assume it’s there”, you can’t get ANYWHERE. You’re stuck with perceptions that have no basis to anything that could be called “objective”. Those perceptions seem to indicate that other entities similar to yourself exist, but of course that’s unreliable, and you have no philosophically good reason to believe that that’s the case. If we really, truly held that level of doubt, we’d be solipsists, and we wouldn’t be bothering to have this conversation because that would be a conversation with your perceptions, which is useless.
In any pragmatic sense, we have to assume that there is an objective reality, with other people, and that one’s senses, on average, give some indication of some part of this objective truth. If we don’t assume this, we can’t even talk meaningfully about science (after all, what is “science” to a solipsist?) or heirarchies of human endeavor or any such thing.
If we agree that there is an objective reality, and we agree that it has the property of predictability (e.g. all else equal, the same initial conditions result in the same cause) (again, not because a universe has to have this property, but because ours seems to, and if we don’t assume that we again don’t get anywhere), then the rest of what I say follows, to varying degrees. Science becomes the study of objective truth.
You point out that a lot of my normative statements have a utilitarian bias. Absolutely. Utilitarianism is a beautiful theory that I have attacked from all sides and never found fault with. Clearly you disagree; but since we can both (presumably?) agree that morality is subjective anyway, there isn’t a big point debating it, except in terms of what matches most closely to rules necessary for societal stabilization, and rules compatible with evolutionary psychology, neither of which I’m guessing you’re interested in.
(And if you don’t agree that morality is subjective, we can probably stop there too, since I doubt we’d get anywhere reconciling that difference.)
Uh oh, are you one of those “science kills mystery” people? I can’t summon up any respect for this point of view, simply because I think anyone who claims this has never actually gotten their hands dirty with science, or met real scientists. I’m a scientist, and I can tell you that the people who work in my field are precisely those with the sort of minds that most people admire in books but don’t have themselves. I don’t mean geniuses beyond all measure or anything silly like that – I mean that scientists are people who are genuinely excited by mystery and the unknown. They throw themselves into this mystery face-first, and don’t come out again until they’ve gotten dirty, explored everything, and seen all the wonder they can find.
On the other hand, people who seem to think that science kills the mystery, I find – and no personal offense is intended – to have a very limited capacity for curiosity. You see a bolt of lightning strike through the air, and you think, the mystery! Is some god angry? Is the sky rending apart? Then you learn that, no, in fact clouds are rubbing together so violently that hundreds of trillions of infinitesimal particles of electricity are surging between the ground and the air, heating the air so quickly that the expansion of the heat causes a heart-stopping boom. To a mind with true curiosity, this should only increase the wonder. How amazing, that such a phenomenon can happen! What are these infinitesimal charged particles? By what mechanism do they travel? Why does rapid expansion of air cause a boom rather than woosh? Why does their travel heat the air? To a mind with real intelligence and curiosity, any answer opens up a hundred new questions, and only increases the mystery. But so many people hear the explanation, and say “oh” as if that explanation settles the matter, and turn away in disappointment. How sad and limiting for them, to lack the fire to quest further into the unknown.
No, as someone who grew up in a culture that cared nothing for science, and then became a scientist myself, I can tell you that those who have dismissed science as “destroying wonder” never seem to have a spark of creativity or brilliance – and that scientists, more than most of the artists, philosophers, or poets I’ve met, often have a wonderful combination of vivid imagination for what could, somehow, somewhere, be possible, and the adventurous drive to explore untrodden ground. They leave their dry-sounding reports behind for those too timid or cowardly or unimaginative to seek for light in the same fashion.