3 January 1667
Cambridge
My dear Isaac,
I read your paper, and I am, I must confess, somewhat nonplussed. What are you doing?
I see that my letter of yesterday was somewhat premature; I should have waited until I had read your paper, since it is in exactly the same category.
You ask: "What is the optimum shape for a wine barrel? Should it be tall and thin, or squat and broad?"
And I ask: "What on Earth difference does it make?"
Surely you are not thinking of becoming a wine merchant? If so, what need is there to waste your time studying mathematics? On the other hand, if you intend to become a mathematician, why should you debase a noble and lofty study by applying it to wine barrels?
As I told you, I have no objection to your making a few pounds by doing minor calculations for the Army, but this is foolishness. You have gone to a great deal of trouble for nothing; as you gain more experience, you will realize the folly of such things.
As to your theory of "fluxions," I admit myself to be completely at a loss. You seem to be assuming that a curve is made up of an infinite number of infinitely small lines. Where is your authority for such a statement? You append no bibliography and no references, and I cannot find it in the literature.
Apparently, you are attempting to handle zero and infinity as though they were arithmetical entities. Where did you learn such nonsense?