 If we take our inspiration from this later Bridgman, we can take him as a guide for a new practice-oriented philosophy of science. We can put aside his reductive doctrine of meaning, his puritanical search for certainty, and his ambivalent privileging of instrumental operations over other types of operations. What Bridgman started up but never quite accomplished in a systematic and complete way was a philosophical analysis of science in terms of activities. Operations provide the philosopher (and the historian) of science with a very useful unit of analysis: actions or events, as opposed to objects, statements, beliefs, theories, paradigms, research programs, etc. The concept of operation should provide an effective framework for incorporating certain highly valuable insights about the nature of scientific practice, including the ideas of Ludwig Wittgenstein (1953) on language-games, Michael Polanyi (1958) on tacit knowledge, Marjorie Grene (1974) on the knowing agent, and Ian Hacking (1983) on direct interventions in experimental investigations.