“We must never make experiments to confirm our ideas, but simply to control them.”

Mediocre men often have the most acquired knowledge. It is in the darker. It is in the darker regions of science that great men are recognized; they are marked by ideas which light up phenomena hitherto obscure and carry science forward.

Experiment is fundamentally only induced observation.

The science of life is a superb and dazzlingly lighted hall which may be reached only by passing through a long and ghastly kitchen.

Our ideas are only intellectual instruments which we use to break into phenomena; we must change them when they have served their purpose, as we change a blunt lancet that we have used long enough.

Now, a living organism is nothing but a wonderful machine endowed with the most marvellous properties and set going by means of the most complex and delicate mechanism.

The eloquence of a scientist is clarity; scientific truth is always more luminous when its beauty is unadorned than when it is tricked out in the embellishments with which our imagination would seek to clothe it.

In science, the best precept is to alter and exchange our ideas as fast as science moves ahead.

We must remain, in a word, in an intellectual disposition which seems paradoxical, but which, in my opinion, represents the true mind of the investigator. We must have a robust faith and yet not believe.

True science teaches us to doubt and, in ignorance, to refrain.

Those who do not know the torment of the unknown cannot have the joy of discovery.

The doubter is a true man of science: he doubts only himself and his interpretations, but he believes in science.

Obervation is a passive science, experimentation is an active science.

The investigator should have a robust faith – and yet not believe.

The fact that knowledge endlessly recedes as the investigator is about to grasp it is what constitutes at the same time his torment and happiness.

If I had to define life in a single phrase, I should clearly express my thought of throwing into relief one characteristic which, in my opinion, sharply differentiates biological science. I should say: life is creation.

First causes are outside the realm of science.

Light confirms my reality, gives birth to my form…without light I am not only invisible but formless as well; and to be unaware of one’s form is to live a death…the truth is the light and light is the truth.

Civilization means conforming to a standard of behavior that may not seem natural to us.

The only distinction that democracies reward is a high degree of conformity.

For us it’s not easy to be conformist, I cannot stand to be conformist, I don’t accept what it is, I like to say no. If I see an injustice I scream.

Believe and be confirmed.

You, a God I worshipped Your word was music to my ears Rose-tinted glasses: verdict You confirmed all my worst fears.

Life, he realize, was much like a song. In the beginning there is mystery, in the end there is confirmation, but it’s in the middle where all the emotion resides to make the whole thing worthwhile.

The mass of men lead lives of quiet desperation. What is called resignation is confirmed desperation.