"The natural system is the highest goal of botany."

"Human beings, having, above all creatures, received the power of reason... need to be aware where nature is unaware. Nature reaches its culmination in humans, but human consciousness has not its essen…"

"The greatest delight is to behold the earth, and to know what it is."

"The calyx is the marriage bed, the corolla the bed-curtains, the filaments the spermatic vessels, the anthers the testes, the pollen the semen, the pistil the vagina, the ovary the uterus, the ovules …"

"If a tree dies, plant another in its place."