Claude Bernard


French Physiologist

Author Quotes

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.

It is impossible to devise an experiment without a preconceived idea; devising an experiment, we said, is putting a question; we never conceive a question without an idea which invites an answer. I consider it, therefore, an absolute principle that experiments must always be devised in view of a preconceived idea, no matter if the idea be not very clear nor very well defined.

Observation, then, is what shows facts; experiment is what teaches about facts and gives experience in relation to anything.

Science rejects the indeterminate.

The goal of scientific physicians in their own science ... is to reduce the indeterminate. Statistics therefore apply only to cases in which the cause of the facts observed is still indeterminate.

Theories are like a stairway; by climbing, science widens its horizon more and more, because theories embody and necessarily include proportionately more facts as they advance.

We must alter theory to adapt it to nature, but not nature to adapt it to theory.?

If I had to define life in a word, it would be: Life is creation.

It is of the greatest importance to consider the influence of the nervous system on the chemical phenomena of the organs, for it is by this influence that the living being is in contact with everything, and everything can then act upon it. There is the true terrain of the influence of mind over matter.

One carries out an observation or experiment, but once the observation or experiment is carried out and confirmed, one reasons, and it is then that all the explanations can present themeselves, as they are coloured by each one's own mind.

Science repulses the indefinite.

The great experimental principle, then, is doubt, that philosophic doubt which leaves to the mind its freedom and initiative, and from which the virtues most valuable to investigators in physiology and medicine are derived.

Theories are only verified hypotheses, verified by more or less numerous facts. Those verified by the most facts are the best, but even then they are never final, never to be absolutely believed.

We must keep our freedom of mind,... and must believe that in nature what is absurd, according to our theories, is not always impossible.

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.

It is said: medicine is the art of healing. Rather, one should say that medicine is the science of healing. The aim of medicine is to arrive at a cure scientifically and not empirically. The problem that medical practice must resolve is thus immense, for it is necessary to embrace both physiology and pathology before one can achieve a scientifically valid treatment.

One enlarges science in two ways: by adding new facts and by simplifying what already exists.

Speaking concretely, when we say ?making experiments or making observations,? we mean that we devote ourselves to investigation and to research, that we make attempts and trials in order to gain facts from which the mind, through reasoning, may draw knowledge or instruction.

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

There are people who seek to find the truth, but there are those who, above all, seek to uncover the errors of their contemporaries.

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

In every enterprise... the mind is always reasoning, and, even when we seem to act without a motive, an instinctive logic still directs the mind. Only we are not aware of it, because we begin by reasoning before we know or say that we are reasoning, just as we begin by speaking before we observe that we are speaking, and just as we begin by seeing and hearing before we know what we see or what we hear.

It is that which we do know which is a great hindrance to our learning that which we do not know.

Our feelings lead us at first to believe that absolute truth must lie within our realm; but study takes from us, little by little, these chimerical conceits.

Speaking in the abstract, when we say ?relying on observation and gaining experience,? we mean that observation is the mind's support in reasoning, and experience the mind's support in deciding, or still better, the fruit of exact reasoning applied to the interpretation of facts. It follows from this that we can gain experience without making experiments, solely by reasoning appropriately about well- established facts, just as we can make experiments and observations without gaining experience, if we limit ourselves to noting facts.

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French Physiologist