Thomas Beddoes to Erasmus Darwin, [late 1793/early 1794]
Dear Sir,
You will not be surprized that an adversary should start up against the whole or against part of’ your 14th section. To debate this matter by letter is, I fear, an impossible undertaking. I will state my principal objections concisely and clearly, if perspicuity in such a disquisition be consistent with brevity.— 1. Mr. Locke has misled you to take general terms for the names of abstract ideas. I deny that we have any idea of time, place, or space; these terms, like cause, necessity, &c. being abbreviations of speech; and if you admit that Berkeley’s, Hume’s, Tooke’s, arguments against abstract ideas are conclusive, you must give up page 114 altogether. If I am right in the explanation I have given of cause and necessity, I cannot be mistaken in my present stricture. If I knew what time, hour, &c. properly meant in any language, it would appear more strikingly true. I do not comprehend how you who have made it so probable that ideas are the motions of the immediate organs of sense could fall into this mistake, but I think you need only to have it suggested to you, to perceive that it is an oversight.—2. After much attention to your reasoning, I cannot perceive any probability in the opinion that ideas resemble external objects; and I do not think this ingenious hypothesis will protect the material world against Berkeley’s Essays and Dialogues. I cannot at present conceive how a motion of an organ of sense can imitate extension, or colour, or any primary or secondary quality of bodies. If I press my finger against the edge of the table, its salient angle will form a retiring angle; but do the nerves of touch move in the form of a salient angle? and (p. 119 of vision) I am equally unable to comprehend how the stimulated part of the retina can exactly resemble the visible figure of the whole tree in miniature. With the figure in the eye, taken out of its orbit, we are all acquainted, but what has this to do with the fibrous motions of the retina; or how can they resemble colour? You will tell me I am doing nothing but making assertions contrary to your’s, but this question must be decided by the report of impressions on the senses; though I think, as far as the argumentum ad hominem goes, you are assailable in this last article by virtue of your own expressions in Sect. 3. What external objects do several sensual motions mentioned there, and their vicissitudes resemble? Is it your opinion that some sensual motions resemble objects, and others not? Then it might have been well to have given a table of each sort; or, at least, a specimen of such a table. The only way in which we judge of external objects is by the coincidence of the senses, or by exerting any one sense for a longer time, &c. in case of doubt. Thus in walking in the night I think I see an object which I am in danger of running against, and I advance my hand or my stick.—3. Much that is said of the spirit of animation I take to be un persiflage, otherwise p. 115 might afford me the opportunity of trying whether there is any resemblance between you and the most celebrated of the Archbishops of Toledo, viz. the one celebrated by Le Sage. All reasoning, however, which attempts to solve a new case by an old axiom is inconclusive. Axioms indeed I think had always be better be kept out of reasoning. Their use at best is to shorten discourse, like that of general terms. They can extend no farther than to cases, each already settled by proper experiments; and to settle any new case, special experiments are requisite. Were I to publish Elements of Geometry, I would not introduce an axiom.
Your’s, with great esteem,
Thomas Beddoes
Published, Stock, Appendix 6, pp. xl–li