What these four thinkers [Oliver Wendell Holmes, William James, Charles S. Pierce, and John Dewey] had in common was not a group of ideas, but a single idea—an idea about ideas. They all believed that ideas are not “out there” waiting to be discovered, but are tools—like forks, knives, and microchips—that people devise to cope with the world in which they find themselves.
They believed that ideas are produced not by individuals, but by groups of individuals—that ideas are social. They believed that ideas do not develop according to some inner logic of their own, but are entirely dependent, like germs, on their human carriers and environment. And they believed that since ideas are provisional responses to particular and unreproducible circumstances, their survival depends not on their immutability but on their adaptability.