In all these things--in the choice of food, place, climate, and recreation--the instinct of self-preservation is dominant, and this instinct manifests itself with least ambiguity when it acts as an instinct of defence. To close one's eyes to much, to seal one's ears to much, to keep certain things at a distance--this is the first principle of prudence, the first proof of the fact that a man is not an accident but a necessity. The popular word for this instinct of defence is _taste._ A man's imperative command is not only to say "no" in cases where "yes" would be a sign of "disinterestedness," but also to say "no" _as seldom as possible._ One must part with all that which compels one to repeat "no," with ever greater frequency. The rationale of this principle is that all discharges of defensive forces, however slight they may be, involve enormous and absolutely superfluous losses when they become regular and habitual. Our greatest expenditure of strength is made up of those small and most frequent discharges of it. The act of keeping things off, of holding them at a distance, amounts to a discharge of strength,--do not deceive yourselves on this point!--and an expenditure of energy directed at purely negative ends. Simply by being compelled to keep constantly on his guard, a man may grow so weak as to be unable any longer to defend himself. Suppose I were to step out of my house, and, instead of the quiet and aristocratic city of Turin, I were to find a German provincial town, my instinct would have to brace itself together in order to repel all that which would pour in upon it from this crushed-down and cowardly world. Or suppose I were to find a large German city--that structure of vice in which nothing grows, but where every single thing, whether good or bad, is squeezed in from outside. In such circumstances should I not be compelled to become a hedgehog? But to have prickles amounts to a squandering of strength; they even constitute a twofold luxury, when, if we only chose to do so, we could dispense with them and open our hands instead....