35 Quotes by Antonie van Leeuwenhoek

How little do we discover in comparison of those things which now are and forever will be hidden from our sight? The whole of which I am fully persuaded no one will ever be able to dive into, and to explain their causes and effects.

We will admit that, out of the mud or sand which is found on the seashore or the beds of our rivers, at low water, shellfish or testaceous animals come forth, but it does not from thence by any means follow that they are produced without any regular course of generation.

I have oft-times been besought, by divers gentlemen, to set down on paper what I have beheld through my newly invented microscopia, but I have generally declined.

I have often endeavoured to view the circulation of the blood in terrestrial animals, but without success, by reason that no parts of their bodies were sufficiently transparent.

For my part, I would say that the male sperm and seeds of plants have been penetrated so far that there is nothing further to discover in this great secret, but I could err in my opinion.

I have lately examined water, in which beaten pepper was steeped, and found two sorts of animals for shape, and each of those sorts to contain greater and smaller kinds: the greater I supposed the elder, the less the younger.

In treating of the oak, I have considered that the species of it growing in warm climates is superior to that which is produced in cold countries. But we must not imagine this to be the case with all woods; on the contrary, the fir timber grown in cold countries is superior to that produced in warm ones, where its growth is rapid.

No one can pretend to say that a fish is ever killed by heat, for many kinds of fish, in the middle of summer, and in the burning heat of the sun, do either play, as it were, on the surface of the water, or hide themselves under the leaves, weeds, or other substances at the bottom.