May 20, 2009
Arguments for corpuscularism:
"Intelligibleness or clearness of Mechanical principles and explications." Other theories "are either so general and slight, or otherwise so unsatisfactory, that, granting their principles, it is very hard to understand or admit their applications of them to particular phenomena."
Unlimited scope. "When I consider the almost innumerable diversifications that compositions and decompositions may make of small number, not perhaps exceeding twenty, of distinct things, I am apt to look upon those who think the Mechanical principles may serve indeed to give an account of the phenomena of this or that particular part of natural philosophy, as statics, hydrostatics, the theory of planetary motions, &c., but can never be applied to all the phenomena of things corporeal---I am apt, I say, to look upon those, otherwise learned, men as I would upon him that should affirm that, by putting together the letters of the alphabet, one may indeed make up all the words to be found in one book, as in Euclid or Virgil, or in one language, as Latin or English, but that they can by no means suffice to supply words to all the books of a great library, much less to all the languages in the world."
Primacy of its principles. "Of the principles of things corporeal, none can be more few, without being insufficient, or more primary, than matter and motion," "neither of them being resoluble into any things whereof it may be truly, or as much a tolerably, said to be compounded." "So that the fear that so much of a new physical hypothesis as is true will overthrow, or make useless, the Mechanical principles, is as if one should fear that there will be a language proposed that is discordant from, or not reducible to, the letters of the alphabet."
Scalability of nature. "And he that looks upon sand in a good microscope will easily perceive that each minute grain of it has as well its own size and shape as a rock or mountain. And when we let fall a great stone and a pebble from the top of a high building, we find not but that the latter as well as the former moves conformably to the laws of acceleration in heavy descending bodies." "And therefore to say that, though in natural bodies whose bulk is manifest and their structure visible the Mechanical principles may be usefully admitted, they are not to be extended to such portions of matter whose parts and textures are invisible, may perhaps look to some as if a man should allow that the laws of mechanism may take place in a town clock, but cannot in a pocket watch, or ... as if, because the terraqueous globe is a vast magnetical body ... one should affirm that magnetical laws are not to be expected to be of force in a spherical piece of loadstone that is not perhaps in inch long."
Against agents. "They that, to solve the phenomena of nature, have recourse to agents ... tell us nothing that will satisfy the curiosity of an inquisitive person, who seeks not so much to know what is the general agent that produces a phenomenon, as by what means, and after what manner, the phenomenon is produced." It is the latter that matters, as witnessed, for example, by the fact that ground corn is the same "whether the corn be ground by a water-mill or a windmill, or a horse-mill, or a hand-mill; that is, by a mill whose stones are turned by inanimate, by brute, or by rational, agents"; or again by the uselessness to "a sober physician, that comes to visit a patient reported to be bewitched, receives of the strange symptoms he meets with and would have an account of, if he be coldly answered that it is a witch or the devil that produces them."