"All men by nature desire knowledge."

• Aristotle (384 BC-322 BC)

"All we know is still infinitely less than all that remains unknown."

• William Harvey (1578-1657)

"Controversy is only dreaded by the advocates of error."

• Benjamin Rush (1745-1813)

"A man who dares to waste one hour of time has not discovered the value of life."

• Charles Darwin (1809-1882)

"Science knows no country, because knowledge belongs to humanity, and is the torch which illuminates the world."

• Louis Pasteur (1822-1892)

"The desire to take medicine is perhaps the greatest feature which distinguishes man from animals."

• Sir William Osler (1849-1919)

"Facts are the air of scientists. Without them you can never fly."

• Linus Pauling (1901-1994)