You are a philosophical researcher who has concluded that the only four metaethical positions that have any serious plausibility are nihilism, Natural Law, Kantianism and utilitarianism. You plan to devote the rest of your life to figuring out which of these four theories is correct. But God speaks to you—and you know it's God speaking—and makes you an offer. First he tells you that you're right that the correct metaethical theory is one of the four you listed. But you must now choose between two options:
- You continue on your career as before, and God makes no guarantee whether you'll come to an answer, and whether, should you come to an answer, the answer will be correct.
- God will tell you which of the four theories is true, and will do so in such a way that you will know that it is God speaking, but the price you will have to pay is that you will lose the creative abilities that are necessary for good philosophical research. Nonetheless, God promises to ensure you will still be able to teach philosophy in a way that is just as beneficial to students and both renumerative and satisfying to yourself.
On the face of it, this is a question whether you love truth more than the search for truth, and my own gut reaction to a question like this is to say: "I want to know the truth, and I don't care about the means by which I get it (except insofar as I am a sinful and vain man, who wants to get it by his own power, but this sinful desire is one that I do not endorse)."
But this gut reaction is simplistic. Aquinas distinguishes faith from science (which includes philosophy, of course, in his terminology) as follows: faith gives one certainty of the truth, but science also gives one understanding of why something is so. Faith ensures that we know with greater certainty that God is a Trinity than we know that the planets move in approximately elliptical orbits; but while our knowledge that God is a Trinity is more certain, we have better understanding of the ellipticity of the orbits—we can say something about why the orbits are elliptical (something about the curvature of space or the law of gravitation). There are pluses and minuses of knowing by faith versus knowing by science: certainty versus understanding.
In choosing option (1), one may never get the right answer; however, one may also get the right answer plus an understanding of why it is the right answer. Option (2) gives one a certainty of knowing the right answer, but it is less likely that one will know why it is the right answer, because one will have lost the creative abilities needed to find that out. It seems, then, that there are incommensurable goods involved in the two options. It may be that both choices are rational.
But suppose now that the offer is different. Option (1) is as before. But in the case of option (2), God will not take away one's philosophical abilities—one will still be free to try to find out why the given metaethical theory is true. While one might worry that knowing the answer ahead of time will make one less good at figuring out the why question (e.g., more apt to glibly accept arguments for the answer one already knows is right), this does not seem to me to be a compelling worry. Barring that worry, it seems that the modified version of option (2) is what one should choose. To fail to opt for option (2) is likely to care more about searching for truth than about having truth, and that, I think, is to have one's priorities backwards.
If this is right, then likewise those philosophers who also know various doctrines by faith need not be shy about making use of this knowledge, about drawing out the entailments of this knowledge. I might work dozens of years trying to figure out if there is such a thing as substance, and fail. But significantly less effort might yield the conclusion that there is substance based on the my knowledge that transsubstantiation occurs (even there, some non-trivial philosophical work is needed to rule out non-substantival accounts of transsubstantiation). And to fail to make use of that knowledge, and instead to search for years, could be a case of loving philosophy more than truth. Of course some will dispute whether we have knowledge by revelation. Here I take my stance by faith: I believe (on the authority of the First Vatican Council, for instance) that faith yields knowledge and proper certainty. (I also have some philosophical stories about how this might happen.)