BE PRAGMATIC

pertaining to the speculator, with his knowledge and interests; and ones pertaining to an evaluator with different knowledge and interests. It is one thing to evaluate Maxwell's imaginary fluid analogue from his perspective in 1855, when no con­firmed electromagnetic theory was known that would unify and explain observable electrical and magnetic phenomena in physical terms.

My view is pragmatic because it allows speculations to be introduced with different purposes and different epi- stemic and non-epistemic situations in mind, and it allows an evaluation of those speculations based on those purposes and situations. In section 2, I noted that Duhem criticized Kelvin's speculations about the molecular nature of the ether as being a “work of imagination,” not “acceptable to reason.” Duhem also criticized both Kelvin and Maxwell for theorizing in physical rather than in purely abstract mathe­matical terms. He called this type of mentality “British,” and he clearly thought it was inferior to the abstract “continental” (or “French”) mind. Theorizing, whether speculative or not, should always be done in the “continental” style, he thought. (Whether this perspective is reasonable is another matter!) Maxwell, too, recognized that there are different sorts of scientific minds:

some minds... can go on contemplating with satisfaction pure quantities presented to the eye by symbols, and to the mind in a form which none but mathematicians can conceive.

But there are others that require that these quantities be represented physically.

For the sake of persons of these different types, scientific truth should be presented in different forms, and should be regarded as equally scientific, whether it appears in the robust form and the vivid colouring of a physical illustration or in the tenuity and paleness of a symbolic expression.^[55]

Maxwell himself strongly preferred physical explana­tions and sought to provide mechanical ones in his theorizing because he regarded them as fundamental. But he recognized that there are other ways to theorize that can be just as good or better for certain minds. There are other, legitimate perspectives from which to theorize and evaluate the result. As far as speculation itself is concerned, yes, it would be great to have “methodized experiments and strict demonstration.” But the “pioneers of science” (including J.C.M.) are often “cut off, for a time” from methodized experiments and strict demonstration. Their “advances, being made, on unknown ground,” are speculative, but advances nonetheless.

Finally, if you are a pragmatist, and you want to provide “methodized experiments and strict demonstration,” how long do you wait? For a pragmatist that is mostly a practical question, the answer to which depends on your interests, your temperament, your time, and your money. It also depends on how likely it is that such experiments can be performed and when, given what is known. Suppose, however, that for some empirical reasons—say, energies required for proper detection are not and may never be achievable (perhaps string theory), or signals from objects postulated can never reach us (multiverse theory)—methodized experiments and strict demonstration will never be possible. Suppose, that is, that there will be no known evidence sufficient to justify be­lief in the speculation. Should you just give up? Should you stop speculating?

Newtonians following the official party line will say: “Of course. Speculations, especially those that will always remain so, ‘have no place in experimental philos­ophy.' ” Pragmatists, however, in the spirit of Maxwell's first paper on molecules, can say, “Not so fast.

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