Claude Bernard Quotes

It is what we know already that often prevents us from learning.

The terrain is everything; the germ is nothing.

Effects vary with the conditions which bring them to pass, but laws do not vary. Physiological and pathological states are ruled by the same forces; they differ only because of the special conditions under which the vital laws manifest themselves.

When entering on new ground we must not be afraid to express even risky ideas so as to stimulate research in all directions. As Priestley put it, we must not remain inactive through false modesty based on fear of being mistaken.

Particular facts are never scientific; only generalization can establish science.

The experimenter who does not know what he is looking for will not understand what he finds.

In a word, I consider hospitals only as the entrance to scientific medicine; they are the first field of observation which a physician enters; but the true sanctuary of medical science is a laboratory; only there can he seek explanations of life in the normal and pathological states by means of experimental analysis.

The first requirement in using statistics is that the facts treated shall be reduced to comparable units.

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.

Proof that a given condition always precedes or accompanies a phenomenon does not warrant concluding with certainty that a given condition is the immediate cause of that phenomenon. It must still be established that when this condition is removed, the phenomen will no longer appear.

Feeling alone guides the mind.

Tout est poison, rien n’est poison, tout est une question de dose. Everything is poisonous, nothing is poisonous, it is all a matter of dose.