So far, I've been having a lot of fun trying to argue the point I tried to make in the previous post. Mostly because everyone is disagreeing with me (at least in some ways), which means I'm in the position of having to make doubly sure I'm getting my points across clearly, and I'm not making an mistakes. This is my idea of a good time.
One thing I want to make clear is this: I'm not arguing for the position that everyone must remain agnostic when faced with an 'expert' claim, on pain of irrationality. Instead I'm arguing for a vastly more modest position, which can be summarized along the following lines:
When faced with a claim about which a person knows nothing or next to nothing, then it's always intellectually acceptable for them to be agnostic about the subject, and this is not necessarily the only intellectually acceptable position. It remains acceptable even if they are faced with expert opinion or consensus.
Let me point out expressly: I am not arguing that agnosticism is mandatory. That's too strong, in my view. Nor am I saying that it's intellectually unacceptable to accept expert or consensus opinion on a matter. Instead, I am - for the moment - arguing for a kind of intellectual pluralism, where multiple responses are, all things being equal, within the realm of reason.
To give an example: Jack and John are told that most cosmologists believe geocentrism has been shown to be true*. Jack accepts the claim 'geocentrism is true'. John is agnostic. Neither Jack nor John have the slightest idea of how to go about determining this for themselves, and both Jack and John are aware that cosmologists study this kind of thing. Both Jack and John are taking a reasonable view. That's not explaining my reasoning, but what I'm concluding and advocating here.
(* For fun, we're placing them a century before Galileo.)
Let's be honest - I have my work cut out for me here. First, I'm arguing that two distinct views can nevertheless be reasonable - not the most popular position to take nowadays. But second, I'm letting John get away with denying scientific consensus, which is pretty high on the list of modern heresies. Worst, I'm doing this as a theist, who regularly work themselves up into a frenzy trying to show how friendly to science they are - so let me say right out, I'm the only theist (indeed, the only person) I'm aware of advocating the views I'm laying out here, and I've done so largely for reasons that have nothing to do with religion or theism.
Either way, on we go.
Despite saying I have my work cut out for me, I think the position I'm outlining has some tremendous intuitive force to it, at least superficially. Really, all I'm saying is that you're not obligated to believe that which you don't understand unless you personally will to do so, or you're dealing with a true figure of moral and intellectual authority - which is going to be either God, or someone named as an authority by God. Lacking that, ultimately, it's up to you to choose to accept whoever's say-so you choose to accept. What can intellectually force your hand is exposure to arguments and evidence that you comprehend and can see the conclusion of - but it's the arguments, the evidence and the comprehension that is key, not someone's second- or third- or fourth-hand judgment of the arguments and evidence.
More than that - trusting a source about an answer to question X is not the same as having knowledge of an answer to question X. Not by a longshot. Likewise, there is a big gulf and a major difference between 'trusting science' and 'trusting these guys who say they did and/or do science'. I find it pretty remarkable that I run into a lot of people who cannot shut up about how much they all trust science, and they never do a bit of it themselves and probably wouldn't know the first thing about DOING any of it themselves. What they trust is that smart people are coming to reasonable conclusions that they've reported accurately, using reasoning that necessarily involves a hell of a lot more than just science. And that's assuming they're not seeking out particular scientists who say what they like to hear, which is quite a risky thing to assume.
So no, they don't trust science. They'd actually have trouble identifying science when they saw it. What they trust are people - individuals and groups - who they assume and hope are doing things right and are reporting things accurately, if that. They trust (what is for them) a vague, broad reasoning process involving human beings who may or may not be trustworthy, biased, and otherwise, which has science as one (there are multiple) central aspect to it. And you know what? In large part, that is fine. I don't hold it against them. But I cannot hold much against the guy who decides that he has no idea how one would even begin to determine the motion (or lack thereof) of the earth, that he doesn't really care to figure out how to do this, and so he's agnostic about the whole thing - no matter what the scientist, or the groups of scientists, say.
Now, one common reply is: but the experts are the ones who have studied a given subject thoroughly. They have presumably investigated the question at length, they have presumably explored the various possible answers, and they have provisionally come to a particular conclusion. Isn't it irrational for you to NOT take them at their word, in light of all that? But the reply there is obvious: I often have no idea what they've studied, how long or sincerely any of them have investigated the question, what answers they ruled in or out as even being possibilities, and more. I do not know what their biases are, individually or collectively. I don't know how reliable their safeguards are for protecting against abuse, if they are even interested in that. I don't even know how intelligent they are, or if they can even reliably tell the difference between what is or is not part of their expertise, or what blindspots they have just by the basis of their knowledge.
For the most part, all I can do is trust them. And I see no reason to simply, broadly and by default give trust to a particular group of men. They do not inherit my trust, or anyone else's, as a graduation present when they get their degree - or at least they shouldn't. That's something I and everyone else give on our own say so. And if they find of it particular importance to convince me or the public at large, then they can make their case if we care to listen to them - and if they fail to make their case, well, so much the worse for their position.
This is an unsettling view to take in some ways, I agree. I happen to think it's far, far less unsettling than the alternative.