The following four documents are sources of the 50 quotations, chosen because they best reflect Bernard's attitudes - his philosophy towards science and humanity. Many of his more specific scientific musings and ideas for projects are also to be found in these resources, especially his cahier rouge:

(*) "An Introduction to the Study of Experimental Medicine" Dover Publications: translated by HC Greene, 1957.

(#) "The Cahier Rouge of Claude Bernard.", Schenkman Publishing: translated by HH Hoff, L Guillemin and R Guillemin.

($)   "Pensées: Notes Detachées".  Bailliere et Fils, 1937: extracts translated by PH Wise 

(+)   Manuscripts, Collège de France.


1.  "Particular facts are never scientific; only generalization can establish science." (*)

2.   "I have been told that I find what I am not looking for, while Helmholtz finds only what he looks for. It is true, but the second direction is bad if it is exclusive." (#)

3.   "True science teaches us to doubt, and in ignoring, to refrain." (*)

4.   "A great discovery is a fact whose appearance in science gives rise to shining ideas, whose light dispels many obscurities and shows us new paths." (*)

5.   "Experiment is fundamentally only induced observation". (*)

6.   "The doubter is a true man of science; he doubts not only himself and his interpretations, but he believes in science." (*)

7.   "In experimentation, it is always necessary to start from a particular fact and proceed to the generalization....but above all, one must observe. (+)

8.   "In the sciences, there is doubtless a very close connection between observation and experimentation. Nevertheless, it is necessary to distinguish them because (otherwise) everything would become confused." (#)

9.   "Among the experiments that may be tried on man, those that can only harm are forbidden, those that are innocent are permissible, and those that may do good are obligatory. It is immoral then, to make an experiment on man when it is dangerous to him, even though the result may be useful to others. It is essentially moral to make experiments on an animal, even though painful and dangerous, if they may be useful to man." (*)

10.  "A litterateur is a man who speaks agreeably about nothing. A scientist who writes well can never be a litterateur because he does not write in order to write, but to say something. The litterateur is a man, who by his specialty sacrifices fundamentals for form." (#)

11.  "Experimental medicine is not a new system of medicine, but on the contrary, is the negation of all systems. A science that halted in a system would remain stationary and would be isolated, because systematization is really scientific encysting, and every encysted part of an organism ceases to take part in that organism's general life." (*)

12.  "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." (#) 

13.  "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." (*)

14. "There are those who believe that criticism consists in attaching oneself to a man, and taking away from him all that he has been able to do of value." (#)

15.  "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." (*)

16.  "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." ($)

17.  "When he does not know what he ought to want, he should know what his enemy wants - and want the contrary." (#)

18. "It is that which we do know which is a great hindrance to our learning that which we do not know." (*)

19. "Everything is drawn through the same die today. It is a way to kill originality. Men need to make themselves by their own efforts." (#)

20. "We must not deceive ourselves: morals do not forbid making experiments on one's neighbour or one's self; in everyday life, men do nothing but experiment on one another." (*)

21.  "The origin of an original work is always the pursuit of a fact which does not fit into accepted ideas." (+)

22.  "Science proceeds by revolution, and not by addition, pure and simple. This holds for theories, which are always successive." (#)

23.  "What we now call an exception is a phenomenon, one or more of whose conditions are unknown. If the conditions of the phenomenon of which we speak were known and determined, there would be no further exceptions: medicine would be as free from them as any other science." (*)

24.  "To make oneself a great reputation, it is necessary to give the belief that one knows only one thing." (#) - quoting Eschricht.

25.  "It is generally agreed that synthesis re-unites what analysis has divided, and that synthesis therefore verifies analysis, of which it is merely the counterproof or necessary complement." (*)

26. "One enlarges science in two ways: by adding new facts and by simplifying what already exists." (#)

27.  "When one calls a new fact a discovery, the fact itself is not a discovery, but rather the new idea derived from it." (*)

28.  "The desire formulates the need; the hypothesis is the need for fact." (#)

29.  "Great men have been compared to giants, upon whose shoulders climb the pygmies - who nevertheless see further than they do." (*)

30.  "False scientists have a great thirst to explain everything, but are not very ardent for proof. They explain everything but never prove anything. They hasten to explain, but not to prove." (#)

31.  "Feeling alone guides the mind and constitutes the primum movens of science. Genius is revealed in a delicate feeling which correctly foresees the laws of natural phenomena. But this we must never forget: the correctness of feeling and the fertility of an idea can be established and proved only by experiment." (*)

32.  "The experiment is complete only after the counterproof, just as analysis is never complete except after synthesis. In physiology we cannot make a synthesis, but we can carry out the control experiment - or counterproof." (#) 

33. "Ideas develop spontaneously in the mind. and when one yields to his thoughts, he is like a man at the window watching the passers by....this requires no effort, and it even has great charm. Where the work is, and the fatigue, is to collar the idea, like one stops the passerby, despite his desire to flee; to retain it, to fix it and give it its character." (#)

34.  "The man of genius is an absurd person, who pushes reasoning to the limit and makes a system. I could be a man of genius, but I do not wish to be: I prefer to be a reasonable man." (#)

35.  "The opinions of other people are a stimulus to us, which arouses others (opinions) in us. It is essentially in this way that they (other people) serve us."  (#).

36.  "Man is forced to be free for this reason alone; that he has a conscience and judgement. His liberty flows from this. He is free to do good or bad; but when he has done bad, remorse proves to him that he was free, and that he could have done otherwise, had he so wished." (#)

37.  "All those who restrict themselves to speaking of experimentation from the fireside do nothing for science; rather they harm it." (#)

38.  "In the organism, physiology is the executive branch; but the legislative branch is creation." (#)

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

40. "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." (#)

41.  "Today no one says any longer 'it is good; that is fine'. No one believes in himself. He says it will sell - or it will not sell." (#) 

42.  "Philosophy concerns itself with the beginning and the end of things. It is those extremes which challenge us. Science does not concern itself with either the beginning or the end: it deals with the present." ($)

43.  "Two things are necessary - science and art, reason and emotion." (#)

44. "There are some doctors who declare themselves against experimentation, and only favour observation. This is erroneous thinking, for experimentation cannot exist without observation. Experiment is only provoked observation, carried further with the aid of instruments and other means of investigation - but basically still observation." ($)

45.  "The defects of the day: no respect for authority; devaluation of all existing reputations. It is the pride of youth and the contempt for the fathers, for the ancients in all the sciences. This is a bad spirit, because we are often only dwarfs standing on their shoulders. They should without doubt not be worshipped, but be known and appreciated." (#)

46.  "...the life of an organism can only continue through the birth of primitive or embryonic cells which mature little by little and then die at a given moment. As it is in organisms, so it is with people. Civilization is essentially a progression towards death. The upper classes do not lose their status. It is necessary that primitive, even barbaric men become civilized and ascend to join them. If this renewal fails to occur, society dies, as would an organism deprived of cellular renewal." ($)

47.  "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?" (#)

48.  "I am convinced that I have also served science in this way: I have stimulated work" (#)

49.  "Art vanishes because it is that mysterious something which moves you without your knowing too much why. There is a certain pleasure in not knowing, because the imagination can go to work." (#)

50.  "I am the leader of the current physiological movement." (#)