Galen

"Excess in any form, whether food, drink, or emotion, leads to disease."

"The body's four humors are like the four elements; all must be present in proper proportion."

"Youth is a time of excess heat and moisture; old age of dryness and cold."

"To heal the sick, one must first understand what it means to be well."

"The physician who fears to question established wisdom will never advance medicine."

"Nature provides the remedy; the physician merely facilitates its application."

"A strong constitution, properly maintained, is better than all the medicines of the world."

"The body speaks a language; the skilled physician learns to understand it."

"In the balance of the humors lies the secret to human longevity."

"Medicine is both an art and a science; master both or master neither."

"The physician's hand must be guided by reason, not by superstition or fear."

"Climate and geography shape the health and temperament of peoples."

"To treat only the symptom while ignoring the cause is the mark of a poor physician."

"The human body is a microcosm of the universe itself."

"Rest and activity must be balanced as carefully as day and night."

"An imbalance in the humors manifests first in the mind before it affects the body."

"The senses are the physician's most valuable instruments of diagnosis."

"A man who masters his appetites has already won half the battle against disease."

"Experience is the true teacher of medicine; theory merely points the way."

"The physician must be willing to learn from every patient, regardless of station."

"Nature's remedies are more powerful than any concoction created in the laboratory."

"To understand the part is to misunderstand the whole; always consider the complete picture."

"The body's natural processes, when understood and respected, guide us toward health."

"A physician who cannot explain his reasoning to his patient is not worthy of trust."

"The mind's power over the body is as real as any medicine, perhaps more so."

"Observation without theory is blind; theory without observation is empty."

"The four seasons correspond to the four stages of human life and the four temperaments."

"To live in opposition to nature is to live in opposition to health."

"The best physicians are those who have suffered illness themselves."

"A fever that comes suddenly may depart just as quickly if nature is properly supported."