"I confess that I have been led to embrace this opinion by a careful consideration of the structure and use of the valves in the veins."

"To search for truth is to search for God."

"The heart does not draw the blood, but propels it."

"It is not wealth or ancestry, but rather the spirit of the age, which has raised me to the highest pinnacle of fame."

"The causes of diseases are often hidden, and to find them requires much labor and diligence."