Variability is the law of life, and as no two faces are the same, so no two bodies are alike, and no two individuals react alike and behave alike under the abnormal conditions which we know as disease. A quote by Canadian physician and medical educator Sir William Osler (1859 - 1919). The quote appears in William Osler: Aphorisms from his bedside teachings and writings, (Henry Schuman; 1950, page 104).