Whatever is known has always seemed systematic, proven, applicable, and evident to the knower. Every alien system of knowledge has likewise seemed contradictory, unproven, inapplicable, fanciful, or mystical. May not the time have come to assume a less egocentric, more general point of view and to speak of comparative epistemology?

Biology taught me that a field undergoing development should be investigated always from the viewpoint of its past development. Who today would study anatomy without embryology? In exactly the same way epistemology without historical and comparative investigations is no more than an empty play on words or an epistemology of the imagination.

In science, just as in art and in life, only that which is true to culture is true to nature.

Thoughts pass from one individual to another, each time a little transformed, for each individual can attach to them somewhat different associations. Strictly speaking, the receiver never understands the thought exactly in the way that the transmitter intended it to be understood. After a series of such encounters, practically nothing is left of the original content. Whose thought is it that continues to circulate?

This social character inherent in the very nature of scientific activity is not without its substantive consequences. Words which formerly were simple terms become slogans; sentences which once were simple statements become calls to battle. This completely alters their socio-cogitative value. They no longer influence the mind through their logical meaning – indeed, they often act against it – but rather they acquire a magical power and exert a mental influence simply by being used.

His basic assumptions were untenable, and his initial experiments irreproducible, yet both were of enormous heuristic value. This is the case with all really valuable experiments. They are all of them uncertain, incomplete, and unique. And when experiments become certain, precise, and reproducible at any time, they no longer are necessary for research purposes proper but function only for demonstration or ad hoc determinations.