Grice e Motterlini

 I am strongly inclined to assent to a principle which might be called a Principle of Economy of Rational Effort. Such a principle would state that where there is a ratiocinative procedure for arriving rationally at certain outcomes, a procedure which, because it is ratiocinative, will involve an expenditure of time and energy, then if there is a nonratiocinative, and so more economical procedure which is likely, for the most part, to reach the same outcomes as the ratiocinative procedure, then provided the stakes are not too high it will be rational to employ the cheaper though somewhat less reliable non-ratiocinative procedure as a substitute for ratiocination. I think this principle would meet with Genitorial approval, in which case the Genitor would install it for use should opportunity arise. (5) On the assumption that it is cha~acteristic of reason to operate on pre-rational states which reason confirms, revises, or even (sometimes) eradicates, such opportunities will arise, provided the rational creatures can, as we can, be trained to modify the relevant pre-rational states or their exercise, so that without actual ratiocination the creatures  84  Paul Grice  can be more or less reliably led by those pre-rational states to the thoughts or actions which reason would endorse were it invoked; with the result that the creatures can do, for the most part, what reason requires without, in the particular case, the voice of reason being heard.