Observation is a passive science, experimentation is an active science.
Science proceeds by revolution, and not by addition, pure and simple. This holds for theories, which are always successive.
The general or mineral world is made for all beings, and in turn each being has below him beings which are made for him, but does he have the feeling that he has something above him, for which he is made?
The true worth of an experimenter consists in his pursuing not only what he seeks in his experiment, but also what he did not seek.
We can learn nothing except by going from the known to the unknown.
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.