"The Road of Excess leads to the Palace of Wisdom".
Progress, as its very etymology declares, means A Step Ahead. It is the Genius, the Eccentric, the Man Who Goes One Better than his fellows, that is the Saviour of the Race. And while it is unwise possibly (in some senses) to exceed in certain respects, we may be sure that he who exceeds in no respect is a mediocrity.
The key of Evolution is Right Variation.
Excess is evidence at least of capacity in the quality at issue. The golf teacher growls tirelessly: "Putt for the back of the hole! Never up, never in!" The application is universal. Far from me be it to deny that excess is too often disastrous. The athlete who dies in his early prime is the skeleton at every Boat Supper. But in such cases the excess is almost always due to the desire to excel other men, instead of referring the matter to the only competent judge, the true Will of the body. I myself used to "go all out" on mountains; I hold more World's Records of various kinds than I can reckon -- for pace, skill, daring, and endurance. But I never worried about whether other people could beat me. For this reason my excesses, instead of causing damage to health and danger to life, turned me from a delicate boy, too frail for football, doomed by my doctors to die in my teens, into a robust ruffian who throve on every kind of hardship and exposure.
On the contrary, every department of life in which, from distaste or laziness, I did not 'exceed', is constantly crippling me in one way or another -- and I recognize with savage remorse that the weakness which I could have corrected so easily in my twenties is in my forties an incurably chronic complaint.