Chemistry is an art that has furnished the world with a great number of useful facts, and has thereby contributed to the improvement of many arts; but these facts lie scattered in many different books, involved in obscure terms, mixed with many falsehoods, and joined to a great deal of false philosophy; so that it is not great wonder that chemistry has not been so much studied as might have been expected with regard to so useful a branch of knowledge, and that many professors are themselves but very superficially acquainted with it. But it was particularly to be expected, that, since it has been taught in universities, the difficulties in this study should have been in some measure removed, that the art should have been put into form, and a system of it attempted—the scattered facts collected and arranged in a proper order. But this has not yet been done; chemistry has not yet been taught but upon a very narrow plan. The teachers of it have still confined themselves to the purposes of pharmacy and medicine, and that comprehends a small branch of chemistry; and even that, by being a single branch, could not by itself be tolerably explained.

I would have you to observe that the difficulty & mystery which often appear in matters of science & learning are only owing to the terms of art used in them, & if many gentlemen had not been rebuted by the uncouth dress in which science was offered to them, we must believe that many of these who now shew an acute & sound judgement in the affairs of life would also in science have excelled many of those who are devoted to it & who were engaged in it only by necessity & a phlegmatic temper. This is particularly the case with respect to chemistry, which is as easy to be comprehended as any of the common affairs of life, but gentlemen have been kept from applying to it by the jargon in which it has been industriously involved.

It is said to be the manner of hypochondriacs to change often their physician …For a physician who does not admit the reality of the disease cannot be supposed to take much pains to cure it.

The great horde of physicians are always servile imitators, who can neither perceive nor correct the faults of their system, and are always ready to growl at and even to worry the ingenious person that could attempt it. Thus was the system of Galen secured in the possession of the schools of physic.

I have lived myself to see the disciples of Hoffman, Boerhaave, Stalh, Cullen, Brown, succeed one another like the shifting figures of a magic lanthern, and their fancies, like the dresses of the annual doll-babies from Paris, becoming from their novelty, the vogue of the day, and yielding to the next novelty their ephemeral favor. The patient, treated on the fashionable theory, sometimes gets well in spite of the medicine.