John McMurry, Organic Chemistry 8th ed. (2012), Ch. 5 : Stereochemistry at Tetrahedral Centers

Pasteur was far ahead of his time. Although the structural theory of Kekulé had not yet been proposed, Pasteur explained his results by speaking of the molecules themselves, saying, “There is no doubt that [in the dextro tartaric acid] there exists an asymmetric arrangement having a nonsuperimposable image. It is no less certain that the atoms of the levo acid have precisely the inverse asymmetric arrangement.” Pasteur's vision was extraordinary, for it was not until 25 years later that his ideas regarding the asymmetric carbon atom were confirmed. Today, we would describe Pasteur's work by saying that he had discovered enantiomers. Enantiomers, also called optical isomers, have identical physical properties, such as melting point and boiling point, but differ in the direction in which their solutions rotate plane-polarized light.

— John McMurry

What It Means

This is a placeholder explanation generated by the low-overhead model. It interprets "Pasteur was far ahead of his time. Although the structural theory of Kekulé had not yet been proposed, Pasteur explained his results by speaking of the molecules themselves, saying, “There is no doubt that [in the dextro tartaric acid] there exists an asymmetric arrangement having a nonsuperimposable image. It is no less certain that the atoms of the levo acid have precisely the inverse asymmetric arrangement.” Pasteur's vision was extraordinary, for it was not until 25 years later that his ideas regarding the asymmetric carbon atom were confirmed. Today, we would describe Pasteur's work by saying that he had discovered enantiomers. Enantiomers, also called optical isomers, have identical physical properties, such as melting point and boiling point, but differ in the direction in which their solutions rotate plane-polarized light." in the context of "John McMurry, Organic Chemistry 8th ed. (2012), Ch. 5 : Stereochemistry at Tetrahedral Centers" to mean that wisdom is timeless.

Source: Wikiquote: "Louis Pasteur" (Quotes about Pasteur: Sorted alphabetically by author or source) The 'What it means' explanation text was generated by Google Gemini Flash (accessed January 18, 2026). https://gemini.google.com/app
Louis Pasteur

About Louis Pasteur

Louis Pasteur (27 December 1822 – 28 September 1895) French microbiologist, chemist, pioneer of the "Germ theory of disease", discoverer of molecular asymmetry and stereo-chemistry, and inventor of the process of Pasteurization.