from Chapter 1, "Is Nothing Sacred", p. 21-22: - Daniel Dennett

From what can "ought" be derived. The most compelling answer is this: ethics must be somehow based on an appreciation of human nature — on a sense of what a human being is or might be, and on what a human being might want to have or want to be. If that is naturalism, then naturalism is no fallacy. No one could seriously deny that ethics is responsive to such facts about human nature. We may just disagree about where to look for the most compelling facts about human nature -n novels, in religious texts, in psychological experiments, in biological or anthropological investigations. The fallacy is not naturalism but, rather, any simple-minded attempt to rush from facts to values. In other words, the fallacy is greedy reductionism of values to facts, rather than reductionism considered more circumspectly, as the attempt to unify our world-view so that out ethical principles don't clash irrationally with the way the world is.

[I]f you want to reason about faith, and offer a reasoned (and reason-responsive) defense of faith as an extra category of belief worthy of special consideration, I'm eager to [participate]. I certainly grant the existence of the phenomenon of faith; what I want to see is a reasoned ground for taking faith as a way of getting to the truth, and not, say, just as a way people comfort themselves and each other (a worthy function that I do take seriously). But you must not expect me to go along with your defense of faith as a path to truth if at any point you appeal to the very dispensation you are supposedly trying to justify. Before you appeal to faith when reason has you backed into a corner, think about whether you really want to abandon reason when reason is on your side. You are sightseeing with a loved one in a foreign land, and your loved one is brutally murdered in front of your eyes. At the trial it turns out that in this land friends of the accused may be called as witnesses for the defense, testifying about their faith in his innocence. You watch the parade of his moist-eyed friends, obviously sincere, proudly proclaiming their undying faith in the innocence of the man you saw commit the terrible deed. The judge listens intently and respectfully, obviously more moved by this outpouring than by all the evidence presented by the prosecution. Is this not a nightmare? Would you be willing to live in such a land? Or would you be willing to be operated on by a surgeon you tells you that whenever a little voice in him tells him to disregard his medical training, he listens to the little voice? I know it passes in polite company to let people have it both ways, and under most circumstances I wholeheartedly cooperate with this benign agreement. But we're seriously trying to get at the truth here, and if you think that this common but unspoken understanding about faith is anything better than socially useful obfuscation to avoid mutual embarrassment and loss of face, you have either seen much more deeply into the issue that any philosopher ever has (for none has ever come up with a good defense of this) or you are kidding yourself.

We alone can be wracked with doubt, and we alone have been provoked by that epistemic itch to seek a remedy: better truth-seeking methods. Wanting to keep better track of our food supplies, our territories, our families, our enemies, we discovered the benefits of talking it over with others, asking questions, passing on lore. We invented culture. Then we invented measuring, and arithmetic, and maps, and writing. These communicative and recording innovations come with a built-in ideal: truth. The point of asking questions is to find true answers; the point of measuring is to measure accurately; the point of making maps is to find your way to your destination. … In short, the goal of truth goes without saying, in every human culture.