cost of logic

Logic may be godlike in its powers, but its diligence is exhausting. You cannot lean on careful logical analysis for every little decision you make; the brain is not metabolically capable of so much careful thought. You must, then, find ways to be guided by emotion and routine for most decisions, without being too far misled by them. Spare the quarter horse of logic for decisions that are more momentous and strange than most, and no more than two or three of them in any one day.