Émile Coué Quote

Auto-suggestion is disconcerting in its simplicity. To the uninitiated, auto-suggestion or self-mastery is likely to appear disconcerting in its simplicity. But does not every discovery, every invention, seem simple and ordinary once it has become vulgarized and the details or mechanism of it known to the man in the street? Not that I am claiming autosuggestion as my discovery. Far from it, auto-suggestion is as old as the hills; only we had forgotten to practice it, and so we needed to learn it all over again.

Chapter I. The reality of auto-suggestion. - Autosuggestion : My method (1923)