Leibniz wrote to Louis Bourguet: "a fable of extravagant proportions"

March 22, 1714

Louis Bourguet (1678-1742) was professor of philosophy and mathematics at Neuch√Ętel after 1731. He wrote on archaeology, geology, philosophy, Biblical scholarship and mathematics. He also tried to integrate Leibnizian philosophy and the tradition of natural philosophy.

Leibniz wrote:

I very much wish that we could go further into the great issue of the generation of animals, which must have an analogy with that of plants. Mr Camerarius of Tubingen thought that their seed is like the ovary, and the pollen (although in the same plant) like the sperm of the male. But even if that were true, the question would always remain whether the basis of the transformation, or the preformed living thing, is in the ovary, following Mr Vallisnieri, or in the sperm, following Mr Leeuwenhoek. For I hold that there must always be a preformed living thing, whether plant or animal, which is the basis of the transformation, and that the same dominant monad be in it.

Bourget must have replied, becauase Leibniz wrote to him on the same day that he wrote a letter to Leeuwenhoek, 5 August 1715:

I would not wish to speak as decisively as you do, Sir, when saying that Mr Leeuwenhoek's view is a fable of extravagant proportions.

Later that month, Bourguet responded.

I am very obliged to you, Sir, for what you have deigned to tell me in favour of Mr Leeuwenhoek, whom I respect greatly. Besides, I by no means intended to offend him when I treated his opinion on spermatic worms as a hollow story. Nevertheless, I am not persuaded by his hypothesis. If I could have easily enclosed my proofs for the propositions I have the honour of sending to you, you would have found in abbreviated form the answer to the objections you have deigned to make to me.

These letters are available in German in Gerhardt, C.I. (ed.) (2010). Die philophischen schriften von Gottfried Wilheim Leibniz, vol. III. For English translations, see http://www.leibniz-translations.com/