Alan Watts suggests a limitation to our ability to make decisions and act “rationally” or “scientifically” in The Way of Zen, pointing instead to the role of intuition, or, in a more general sense, that which is undefinable (emphasis mine):
Indeed, an exponent of the I Ching [a fundamental ancient Chinese text] might give us quite a tough argument about the relative merits of our ways for making important decisions. We feel that we decide rationally because we base our decisions on collecting relevant data about the matter in hand. We do not depend upon such irrelevant trifles as the chance tossing of a coin, or the patterns of tea leaves or cracks in a shell [a traditional method of divination]. Yet he might ask whether we really know what information is relevant, since our plans are constantly upset by utterly unforeseen incidents. He might ask how we know when we have collected enough information upon which to decide. If we were rigorously “scientific” in collecting information for our decisions, it would take us so long to collect the data that the time for action would have passed long before the work had been completed. So how do we know when we have enough? Does the information itself tell us that it is enough? On the contrary, we go through the motions of gathering the necessary information in a rational way, and then, just because of a hunch, or because we are tired of thinking, or because the time has come to decide, we act. He would ask whether this is not depending just as much upon “irrelevant trifles” as if we had been casting the yarrow stalks [another form of divination].
In other words, the “rigorously scientific” method of predicting the future can be applied only in special cases – where prompt action is not urgent, where the factors involved are largely mechanical, or in circumstances so restricted as to be trivial. By far the greater part of our important decisions depend upon “hunch” – in other words, upon the “peripheral vision” of the mind. Thus the reliability of our decisions rests ultimately upon our ability to “feel” the situation, upon the degree to which this “peripheral vision” has been developed.
How often are we really able to rely on a truly “scientific” process to decision making and action? By my estimation, much less often than we’d like to admit.
EDIT: Andrew Sullivan (6/24) points to Marilynne Robinson:
I think it’s probably a lot like meditation—which I have never practiced. But from what I understand, it is a capacity that develops itself and that people who practice it successfully have access to aspects of consciousness that they would not otherwise have. They find these large and authoritative experiences. I think that, by the same discipline of introspection, you have access to a much greater part of your awareness than you would otherwise. Things come to mind. Your mind makes selections—this deeper mind—on other terms than your front-office mind. You will remember that once, in some time, in some place, you saw a person standing alone, and their posture suggested to you an enormous narrative around them. And you never spoke to them, you don’t know them, you were never within ten feet of them. But at the same time, you discover that your mind privileges them over something like the Tour d’Eiffel. There’s a very pleasant consequence of that, which is the most ordinary experience can be the most valuable experience. If you’re philosophically attentive you don’t need to seek these things out.