Chemistry, which made possible plastics, synthetic fibers, and many other innovations, also greatly affected daily life by its impact on food, clothing, and most material objects. Chemistry assisted the very great gains made by the biological sciences and their application to medicine and public health.
Twentieth-Century Thought and Letters
Perhaps the great scientific event of the twentieth century was the revolution in physics symbolized for the public by Albert Einstein (1879-1955). This revolution centered on radical revisions made in the Newtonian world-machine, the mechanistic model of the universe that had been accepted for more than two centuries.
In the twentieth century each science, and each branch of each science, continued its ever more intense specialization. Cooperation among pure scientists, applied scientists, engineers, bankers, business people, and government officials produced exponential increases.
Probably the most widespread philosophical movement of the century developed on the margin of formal philosophy and the social sciences. This movement is called historicism—the attempt to find in history an answer to those ultimate questions of the structure of the universe and of human fate that the philosopher has always asked.
A philosophy known as existentialism developed from such nineteenth-century sources as Nietzsche and the Danish theologian Soren Kierkegaard (1813-1855), who assailed the dehumanizing effects of the increasingly materialistic society of his day. In such works as Fear and Trembling (1843) and Either/Or (also 1843), he argued that Christian truth was not to be found in churches but in experiencing extreme human conditions through the act of existence.
In the social sciences, the twentieth century continued to question its inheritance of faith in the basic reasonableness and goodness of human nature. In fact, some social scientists found the term human nature to be so all-embracing as to make no sense.
The specific programs and values of twentieth-century thinkers in this broad field were very varied. Yet most of them had a sense of the subtlety, the complexities, the delicacy—and the toughness and durability—of the forces that bind human beings together in society but also hold them apart.