Ardent desire for knowledge, in fact, is the one motive attracting and supporting investigators in their efforts; and just this knowledge, really grasped and yet always flying before them, becomes at once their sole torment and their sole happiness …. A man of science rises ever, in seeking truth; and if he never finds it in its wholeness, he discovers nevertheless very significant fragments; and these fragments of universal truth are precisely what constitutes science.
Quotations by:
Bernard, Claude
When we meet a fact which contradicts a prevailing theory, we must accept the fact and abandon the theory, even when the theory is supported by great names and generally accepted.
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.
Indeed, 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 phenomenon will no longer appear.
But it happens further quite naturally that men who believe too firmly in their theories, do not believe enough in the theories of others. So the dominant idea of these despisers of their fellows is to find others’ theories faulty and to try to contradict them. […] They make experiments only to destroy a theory, instead of to seek the truth. At the same time, they make poor observations, because they choose among the results of their experiments only what suits their object, neglecting whatever is unrelated to it, and carefully setting aside everything which might tend toward they idea they wish to combat.
[Mais il arrive encore tout naturellement que ceux qui croient trop à leurs théories ne croient pas assez à celles des autres. Alors l’idée dominante de ces contempteurs d’autrui est de trouver les théories des autres en défaut et de chercher à les contredire. […] Ils ne font des expériences que pour détruire une théorie, au lieu de les faire pour chercher la vérité. Ils font également de mauvaises observations, parce qu’ils ne prennent dans les résultats de leurs expériences que ce qui convient à leur but, en négligeant ce qui ne s’y rapporte pas, et en écartant bien soigneusement tout ce qui pourrait aller dans le sens de l’idée qu’ils veulent combattre.]
Claude Bernard (1813-1878) French physiologist, scientist
An Introduction to the Study of Experimental Medicine [Introduction à l’Étude de la Médecine Expérimentale], ch. 3 (1865) [tr. Greene (1957)]
(Source)
(Source (French)). Other translation:But it still happens quite naturally that those who believe too strongly in their own theories don't believe enough in those of others. The dominant idea of these detractors of others is to find flaws in other people's theories and to try to contradict them. [...] They conduct experiments only to disprove a theory, instead of doing so to seek the truth. They also make flawed observations because they only select from the results of their experiments what suits their purpose, neglecting what is irrelevant, and carefully disregarding anything that might support the idea they want to refute.
[Google Translate]
Men who have excessive faith in their theories or ideas are not only ill prepared for making discoveries; they also make very poor observations. Of necessity, they observe with a preconceived idea, and when they devise an experiment, they can see, in its results, only a confirmation of their theory. In this way they distort observation and often neglect very important facts because they do not further their aim.
[Les hommes qui ont une foi excessive dans leurs théories ou dans leurs idées sont non-seulement mal disposés pour faire des découvertes, mais ils font aussi de très-mauvaises observations. Ils observent nécessairement avec une idée préconçue, et quand ils ont institué une expérience, ils ne veulent voir dans ses résultats qu’une confirmation de leur théorie. Ils défigurent ainsi l’observation et négligent souvent des faits très-importants, parce qu’ils ne concourent pas à leur but.]
Claude Bernard (1813-1878) French physiologist, scientist
An Introduction to the Study of Experimental Medicine [Introduction à l’Étude de la Médecine Expérimentale], ch. 3 (1865) [tr. Greene (1957)]
(Source)
You need not hesitate to say aloud that my adversary is wrong and that he is an imbecile.
[Vous ne devez pas hésiter à dire hautement que mon adversaire a tort et que c’est un imbécile.]
Claude Bernard (1813-1878) French physiologist, scientist
Cahier de Notes (1860) [tr. Hoff / Guillemin / Guillemin (1967)]
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