Correspondence, by Benedict de Spinoza, [1883], at sacred-texts.com
[Oldenburg propounds several questions concerning God and His existence, thought, and the axioms of Eth. I. He also informs Spinoza of a philosophical society, and promises to send Boyle's book.]
Most Excellent Friend, Your learned letter has been delivered to me, and read with great pleasure.
I highly approve of your geometrical method of proof,
but I must set it down to my dulness, that I cannot follow with readiness what you set forth with such accuracy. Suffer me, then, I beg, to expose the slowness of my understanding, while I put the following questions, and beg of you to answer them.
First. Do you clearly and indisputably understand solely from the definition you have given of God, that such a Being exists? For my part, when I reflect that definitions contain only the conceptions formed by our minds, and that our mind forms many conceptions of things which do not exist, and is very fertile in multiplying and amplifying what it has conceived, I do not yet see, that from the conception I have of God I can infer God's existence. I am able by a mental combination of all the perfections I perceive in men, in animals, in vegetables, in minerals, &c., to conceive and to form an idea of some single substance uniting in itself all such excellences; indeed my mind is able to multiply and augment such excellences indefinitely; it may thus figure forth for itself a most perfect and excellent Being, but there would be no reason thence to conclude that such a Being actually exists.
Secondly. I wish to ask, whether you think it unquestionable, that body cannot be limited by thought, or thought by body; seeing that it still remains undecided, what thought is, whether it be a physical motion or a spiritual act quite distinct from body?
Thirdly. Do you reckon the axioms, which you have sent to me, as indemonstrable principles known by the light of nature and needing no proof? Perhaps the first is of this nature, but I do not see how the other three can be placed in a like category. The second assumes that nothing exists in the universe save substances and accidents, but many persons would say that time and place cannot be classed either as one or the other. Your third axiom, that things having different attributes have no quality in common, is so far from being clear to me, that its contrary seems to be shown in the whole universe. All things known to us agree in certain respects and differ in others. Lastly, your fourth axiom, that when things have no quality in common, one cannot be produced by another, is not so plain to my groping intelligence as to stand in need of no further illumination.
[paragraph continues] God has nothing actually in common with created things, yet nearly all of us believe Him to be their cause.
As you see that in my opinion your axioms are not established beyond all the assaults of doubt, you will readily gather that the propositions you have based upon them do not appear to me absolutely firm. The more I reflect upon them, the more are doubts suggested to my mind concerning them.
As to the first, I submit that two men are two substances with the same attribute, inasmuch as both are rational; whence I infer that there can be two substances with the same attribute.
As to the second, I opine that, as nothing can be its own cause, it is hardly within the scope of our intellect to pronounce on the truth of the proposition, that substance cannot be produced even by any other substance. Such a proposition asserts all substances to be self-caused, and all and each to be independent of one another, thus making so many gods, and therefore denying the first cause of all things. This, I willingly confess, I cannot understand, unless you will be kind enough to explain your theory on this sublime subject somewhat more fully and simply, informing me what may be the origin and mode of production of substances, and the mutual interdependence and subordination of things. I most strenuously beg and conjure you by that friendship which we have entered into, to answer me freely and faithfully on these points; you may rest assured, that everything which you think fit to communicate to me will remain untampered with and safe, for I will never allow anything to become public through me to your hurt or disadvantage. In our philosophical society we proceed diligently as far as opportunity offers with our experiments and observations, lingering over the compilation of the history of mechanic arts, with the idea that the forms and qualities of things can best be explained from mechanical principles, and that all natural effects can be produced through motion, shape, and consistency, without reference to inexplicable forms or occult qualities, which are but the refuge of ignorance.
I will send the book I promised, whenever the Dutch Ambassadors send (as they frequently do) a messenger to
the Hague, or whenever some other friend whom I can trust goes your way. I beg you to excuse my prolixity and freedom, and simply ask you to take in good part, as one friend from another, the straightforward and unpolished reply I have sent to your letter, believing me to be without deceit or affectation,
Yours most faithfully,
HENRY OLDENBURG.
London, 27 Sept., 1661.