Quotes from Jean-Baptiste Lamarck

Habits form a second nature.

All knowledge that is not the real product of observation, or of consequences deduced from observation, is entirely groundless and illusory.

What nature does in the course of long periods we do every day when we suddenly change the environment in which some species of living plant is situated.

It is not always the magnitude of the differences observed between species that must determine specific distinctions, but the constant preservation of those differences in reproduction.

It is not enough to discover and prove a useful truth previously unknown, but that it is necessary also to be able to propagate it and get it recognized.