 One lesson we can take from Bridgman’s troubles is that meaning is unruly and promiscuous. The kind of absolute control on the meaning of scientific concepts that Bridgman wished for is not possible. The most control that can be achieved is for the scientific community to agree on an explicit definition and to respect it. But even firm definitions can only constrain the uses of a concept. The entire world can agree to define length by the standard meter in Paris (or by the wavelength of a certain atomic radiation), and that still comes nowhere near exhausting all that we mean by length. Bridgman himself later specifically admitted that his statement that meanings were synonymous with operations was “obviously going too far when taken out of context” (1938, 117). Especially compared with the notion of “meaning as use,” often traced back to the later phase of Ludwig Wittgenstein’s  work,[3]  it is easy to recognize the narrowness of Bridgman’s initial ideas. Bridgman’s later gloss on his ideas was in fact rather late-Wittgensteinian: “To know the meaning of a term used by me it is evident, I think, that I must know the conditions under which I would use the term” (1938, 116). As measurement operations provide only one specific context in which a concept is used, operational definitions can only cover one particular aspect of meaning.