George Berkeley to Samuel Johnson
[Nov. 25, 1729]
The ingenious letter you favoured me with found me very much indisposed with a gathering or imposthumation in my head, which confined me several weeks, and is now, I thank God, relieved. The objections of a candid thinking man to what I have written will always be welcome, and I shall not fail to give all the satisfaction I am able, not without hopes of convincing or being convinced. It is a common fault for men to hate opposition, and be too much wedded to their own opinions. I am so sensible of this in others that I could not pardon it to myself if I considered mine any further than they seem to me to be true; which I shall the better be able to judge of when they have passed the scrutiny of persons so well qualified to examine them as you and your friends appear to be, to whom my illness must be an apology for not sending this answer sooner.
1 The true use and end of Natural Philosophy is to explain the phenomena of nature; which is done by discovering the laws of nature, and reducing particular appearances to them. This is Sir Isaac Newton's method; and such method or design is not in the least inconsistent with the principles I lay down. This mechanical philosophy doth not assign or suppose any one natural efficient cause in the strict and proper sense; nor is it, as to its use, concerned about matter; nor is matter connected therewith; nor doth it infer the being of matter. It must be owned, indeed, that the mechanical philosophers do suppose (though unnecessarily) the being of matter. They do even pretend to demonstrate that matter is proportional to gravity, which, if they could, this indeed would furnish an unanswerable objection. But let us examine their demonstration. It is laid down in the first place, that the momentum of any body is the product of its quantity by its velocity, moles in celeritatem ducta. If, therefore, the velocity is given, the momentum will be as its quantity. But it is observed that bodies of all kinds descend in vacuo with the same velocity; therefore the momentum of descending bodies is as the quantity or moles, i.e. gravity is as matter. But this argument concludes nothing, and is a mere circle. For, I ask, when it is premised that the momentum is equal to the moles in celeritatem ducta, how the moles or quantity of matter is estimated? If you say, by extent, the proposition is not true; if by weight, then you suppose that the quantity of matter is proportional to matter; i.e. the conclusion is taken for granted in one of the premises. As for absolute space and motion, which are also supposed without any necessity or use, I refer you to what I have already published; particularly in a Latin treatise, De Motu, which I shall take care to send to you.
2 Cause is taken in different senses. A proper active efficient cause I can conceive none but Spirit; nor any action, strictly speaking, but where there is Will. But this doth not hinder the allowing occasional causes (which are in truth but signs); and more is not requisite in the best physics, i.e. the mechanical philosophy. Neither doth it hinder the admitting other causes besides God; such as spirits of different orders, which may be termed active causes, as acting indeed, though by limited and derivative powers. But as for an unthinking agent, no point of physics is explained by it, nor is it conceivable.
3 Those who have all along contended for a material world have yet acknowledged that natura naturans (to use the language of the Schoolmen) is God; and that the divine conservation of things is equipollent to, and in fact the same thing with, a continued repeated creation: in a word, that conservation and creation differ only in the terminus a quo. These are the common opinions of the Schoolmen; and Durandus, who held the world to be a machine like a clock, made and put in motion by God, but afterwards continuing to go of itself, was therein particular, and had few followers. The very poets teach a doctrine not unlike the schools - Mens agitat molem (Virg. Aeneid VI). The Stoics and Platonists are everywhere full of the same notion. I am not therefore singular in this point itself, so much as in my way of proving it. Further, it seems to me that the power and wisdom of God are as worthily set forth by supposing Him to act immediately as an omnipresent infinitely active Spirit, as by supposing Him to act by the mediation of subordinate causes, in preserving and governing the natural world. A clock may indeed go independent of its maker or artificer, inasmuch as the gravitation of its pendulum proceeds from another cause, and that the artificer is not the adequate cause of the clock; so that the analogy would not be just to suppose a clock is in respect of its artist what the world is in respect of its Creator. For aught I can see, it is no disparagement to the perfections of God to say that all things necessarily depend on Him as their Conservator as well as Creator, and that all nature would shrink to nothing, if not upheld and preserved in being by the same force that first created it. This I am sure is agreeable to Holy Scripture, as well as to the writings of the most esteemed philosophers; and if it is to be considered that men make use of tools and machines to supply defect of power in themselves, we shall think it no honour to the Divinity to attribute such things to Him.
4 As to guilt, it is the same thing whether I kill a man with my hands or an instrument; whether I do it myself or make use of a ruffian. The imputation therefore upon the sanctity of God is equal, whether we suppose our sensations to be produced immediately by God, or by the mediation of instruments and subordinate causes, a which are His creatures, and moved by His laws. This theological consideration, therefore, may be waved, as leading beside the question; for such I hold all points to be which bear equally hard on both sides of it. Difficulties about the principle of moral actions will cease, if we consider that all guilt is in the will, and that our ideas, from whatever cause they are produced, are alike inert.
5 As to the art and contrivance in the parts of animals, &c., I have considered that matter in the Principles of Human Knowledge, and, if I mistake not, sufficiently shewn the wisdom and use thereof, considered as signs and means of information. I do not indeed wonder that on first reading what I have written, men are not thoroughly convinced. On the contrary, I should very much wonder if prejudices, which have been many years taking root, should be extirpated in a few hours' reading. I had no inclination to trouble the world with large volumes. What I have done was rather with a view of giving hints to thinking men, who have leisure and curiosity to go to the bottom of things, and pursue them in their own minds. Two or three times reading these small tracts, and making what is read the occasion of thinking, would, I believe, render the whole familiar and easy to the mind, and take off that shocking appearance which hath often been observed to attend speculative truths.
6 I see no difficulty in conceiving a change of state, such as is vulgarly called Death, as well without as with material substance. It is sufficient for that purpose that we allow sensible bodies, i.e. such as are immediately perceived by sight and touch; the existence of which I am so far from questioning (as philosophers are used to do), that I establish it, I think, upon evident principles. Now, it seems very easy to conceive the soul to exist in a separate state (i.e. divested from those limits and laws of motion and perception with which she is embarrassed here), and to exercise herself on new ideas, without the intervention of these tangible things we call bodies. It is even very possible to apprehend how the soul may have ideas of colour without an eye, or of sounds without an ear.
And now, Sir, I submit these hints (which I have hastily thrown together as soon as my illness gave me leave) to your own maturer thoughts, which after all you will find the best instructors. What you have seen of mine was published when I was very young, and without doubt hath many defects. For though the notions should be true (as I verily think they are), yet it is difficult to express them clearly and consistently, language being framed to common use and received prejudices. I do not therefore pretend that my books can teach truth. All I hope for is, that they may be an occasion to inquisitive men of discovering truth, by consulting their own minds, and looking into their own thoughts. As to the Second Part of my treatise concerning the Principles of Human Knowledge, the fact is that I had made a considerable progress in it; but the manuscript was lost about fourteen years ago, during my travels in Italy, and I never had leisure since to do so disagreeable a thing as writing twice on the same subject.
Objections passing through your hands have their fun force and clearness. I like them the better. This intercourse with a man of parts and philosophic genius is very agreeable. I sincerely wish we were nearer neighbours. In the meantime, whenever either you or your friends favour me with their thoughts, you may be sure of a punctual correspondence on my part. Before I have done I will venture to recommend these points: (1) To consider well the answers I have already given in my books to several objections. (2) To consider whether any new objection that shall occur doth not suppose the doctrine of abstract general ideas. (3) Whether the difficulties proposed in objection to my scheme can be solved by the contrary; for if they cannot, it is plain they can be no objections to mine.
I know not whether you have got my treatise concerning the Principles of Human Knowledge. I intend to send it to you with my tract De Motu. My humble service to your friends, to whom I understand I am indebted for some part of your letter.
I am your faithful humble servant,