Feeling Alone Guides The Mind.

All The Vital Mechanisms, Varied As They Are, Have Only One Object, That Of Preserving Constant The Conditions Of Life In The Internal Environment.

We Must Keep Our Freedom Of Mind, ... And Must Believe That In Nature What Is Absurd, According To Our Theories, Is Not Always Impossible.

Hatred Is The Most Clear- Sighted, Next To Genius.

Well-observed Facts, Though Brought To Light By Passing Theories, Will Never Die; They Are The Material On Which Alone The House Of Science Will At Last Be Built.

We Must Never Make Experiments To Confirm Our Ideas, But Simply To Control Them.