An example of a historical scientific idea (vitalism), now considered to be an alternative conception:
"…Friedrich Woehler's head…had heard discussions in every scientific circle he had visited of a mysterious vital force, as elusive as phlogiston.
Inside the living body of plants and animals, it was thought, burned a steady invisible flame, and through this flame a mysterious vital force built up the sugars, the starches, the proteins and hundreds of other very complex compounds. This vague creative force existed in the animal and vegetable kingdoms but not in the mineral world. Men believed that the substances which constituted the texture of vegetation differed from mineral substances in that the former could not be built up or synthesized in the laboratory….Some even doubted whether these organic compounds obeyed the laws of chemistry. Such was the prevailing opinion of the world in 1828."
Bernard Jaffe (1934) Crucibles. The Lives and Achievements of the Great Chemists. Jarrolds Publishers.
