On Theories (1860-1874)

“The world little knows how many of the thoughts and theories which have passed through the mind of a scientific investigator have been crushed in silence and secrecy; that in the most successful instances not a tenth of the suggestions, the hopes, the wishes, the preliminary conclusions have been realized.” (Michael Faraday, “The Forces of Matter”, 1860)

“Observation is so wide awake, and facts are being so rapidly added to the sum of human experience, that it appears as if the theorizer would always be in arrears, and were doomed forever to arrive at imperfect conclusion; but the power to perceive a law is equally rare in all ages of the world, and depends but little on the number of facts observed.” (Henry Thoreau, “A Week on the Concord and Merrimack Rivers”, 1862) 

“If an idea presents itself to us, we must not reject it simply because it does not agree with the logical deductions of a reigning theory.” (Claude Bernard, "An Introduction to the Study of Experimental Medicine", 1865)

"Science asks no questions about the ontological pedigree or a priori character of a theory, but is content to judge it by its performance; and it is thus that a knowledge of nature, having all the certainty which the senses are competent to inspire, has been attained - a knowledge which maintains a strict neutrality toward all philosophical systems and concerns itself not with the genesis or a priori grounds of ideas." (Chauncey Wright, "The Philosophy of Herbert Spencer", North American Review, 1865)

 “Step by step we cross great eras in the development of thought: there is no sudden gigantic stride; a theory proceeds by slow evolution until it dominates or is destroyed.” (George F Rodwell, “Theory of Phlogiston”, ‘The London, Edinburgh, and Dublin Philosophical Magazine and Journal of Science’ 35, 1868)

"Isolated facts and experiments have in themselves no value, however great their number may be. They only become valuable in a theoretical or practical point of view when they make us acquainted with the law of a series of uniformly recurring phenomena, or, it may be, only give a negative result showing an incompleteness in our knowledge of such a law, till then held to be perfect." (Hermann von Helmholtz, "The Aim and Progress of Physical Science", 1869)

 “The triumph of a theory is to embrace the greatest number and the greatest variety of facts.” (Charles A Wurtz, “A History of Chemical Theory from the Age of Lavoisier to the Present Time”, 1869)

“The aim of natural science is to obtain connections among phenomena. Theories, however, are like withered leaves, which drop off after having enabled the organism of science to breathe for a time." (Ernst Mach, “Die Geschichte und die Wurzel des Satzes von der Erhaltung der Arbeit”, 1871)