Against this background, Pasteur did his epochal work confirming and extending the earlier experiments on the preeminence of the living yeast cell. In the 30-year war of words with his enemies in chemistry, Pasteur emerged the clear victor, but at an intolerable cost. Pasteur, who as a youth discovered stereochemistry, now allied himself with vitalism.

The basic medical sciences, which in my school days were completely discrete from one another, have now effectively been merged into a single discipline. This astonishing development, this unification, is based largely on the expression of anatomy, pathology, bacteriology, and physiology in a common tongue, the language of chemistry. Anatomy, the most descriptive of these sciences, and genetics, the most abstract, are now simply chemistry. Anatomy is studied as a continuous progression from molecules of modest size to the macromolecular assemblies, organelles, cells, and tissues that make up a functioning organism.

Where has the development of this new branch of biochemistry, called molecular biology, fallen short? In its rapid and turbulent growth, molecular biology has washed away much of the bridge to chemistry. In the rush and excitement over the new mastery over DNA, attention in biochemistry departments has been sharply shifted to major biological problems of cell growth and development and away from chemistry. Training in enzymology and its practice have been neglected. Most biochemistry and molecular biology students are introduced to enzymes as commercial reagents and treat them as faceless as buffers and salts. As long as this inattention to enzyme chemistry and basic biochemistry persists, the fundamental issues of cell growth and development will not be resolved and their application to degenerative diseases and aging will be delayed.

Molecular biology falters when it ignores the chemistry of the products of the DNA blueprint-the enzymes and proteins, and their products-the integrated machinery and framework of the cell. Molecular biology appears to have broken into the bank of cellular chemistry, but for lack of chemical tools and training, it is still fumbling to unlock the major vaults.

We now have the paradox of the two cultures, chemistry and biology, growing farther apart even as they discover more common ground. For the chemists, the chemistry of biological systems is either too mundane or too complex. As a result, they are drawn in the opposite direction, toward a deeper physical understanding of atomic and molecular behavior. With occasional gestures in the direction of biology, chemistry departments still retain the classical separations into discrete divisions of organic, physical, and inorganic-analytical chemistry. Perhaps they can now ignore the analysis and synthesis of proteins and nucleic acids because these procedures have become straightforward enough to be machine-programmed and operated. But the structure-function relationship of these macromolecules is another matter. Polymer chemists, for example, are frightened away not only by the size and complexity of nucleic acids and proteins but even more by their intimate association with water molecules, a habitat which introduces unacceptable complications into otherwise satisfactory calculations.

In these research studies, the effects of manipulating the cell’s genome and the actions of viruses and various agents are almost always monitored with intact cells and organisms. Rarely is an attempt made to examine a stage in an overall process in a cell-free system. This reliance in current biological research on intact cells and organisms to fathom their chemical operations is a modern example of the “vitalism” that befell Pasteur a century ago and that has permeated the attitudes of every generation of biologists before and since.

In a cross-cultural forum provided by a recent meeting of the American Association for the Advancement of Science, I was led to wonder whether a sociological study of chemists and biologists might be helpful in understanding their different styles. Are chemists more conservative, analytical, and clannish than biologists? Are biologists more artistic, eclectic, and right-brain dominated than chemists? Which of the language barriers is more formidable and needs earlier imprinting? How much of the cultural difference between chemists and biologists is attributable to highly evolved training and vocational patterns? What are the consequences of most chemists being employed in industry and most biologists in academia? This sociological investigation could start off without threat of racial, political, or sexual opposition. Insights gained from such a study might be useful for science training and practice in the future.

In the long view, these cultural differences between chemistry and biology are dwarfed by our overall devotion to the larger culture of science. It is the discipline of science that enables ordinary people, whether chemists or biologists, to go about doing the ordinary things, which, when assembled, reveal the extraordinary intricacies and awesome beauties of nature. Science not only permits them to contribute to grand enterprises but also offers them a changing and endless frontier for exploration. I like the remark of Einstein, who has proven as quotable in philosophy as in physics. He once said: “The most beautiful experience we can have is the mysterious. It is the fundamental emotion that stands at the cradle of true art and true science. Whoever does not know it and can no longer wonder, no longer marvel, is as good as dead.”