William Harvey — "It is a thing worthy of observation how much more easily and quickly the mind is…"
It is a thing worthy of observation how much more easily and quickly the mind is deceived than the eye.
Get This Quote & Author's Image Illustrated On:
Click any product to generate a realistic preview. Up to 3 at a time.
* Initial load can take up to 90 seconds — revising the preview in another color is nearly instant.
Kitchen
Apparel
Other
More from William Harvey
"The most important thing in life is to be useful."
"The left ventricle of the heart ejects blood into the aorta."
"I profess both to learn and to teach anatomy not from books but from dissections; not from the tenets of philosophers but from the fabric of nature."
"The egg is the common origin of all animals."
"The blood is the source of life, and the heart is the fountain thereof."
About William Harvey (1578-1657)
English physician whose On the Motion of the Heart and Blood in Animals (1628) demonstrated blood circulation, overturning 1,400 years of Galenic medicine. Closely associated with Francis Bacon (his contemporary in the new English empiricism). For an intellectual contrast, see Galenic medicine, the 2nd-century Greek medical tradition (humors, blood-as-consumed-fuel) — Harvey calculated that the heart pumps more blood per hour than the body could possibly produce as fuel — a single quantitative observation that demolished the entire Galenic-Aristotelian medical worldview. The cleanest example in medical history of arithmetic disproving 14 centuries of authority.
Details
A statement on the pitfalls of intellectual bias versus direct empirical observation.
Date: c. 1650s (attributed)
WisdomVerification
Unverifiable
Found in 1 providers: gemini
1 source checked
Understanding this quote
What it means
The quote argues that inherited assumptions and abstract reasoning mislead us far more readily than direct sensory observation. When we theorize or rely on received doctrine, we deceive ourselves effortlessly. But when we look carefully at the actual world — measuring, watching, comparing — reality resists distortion. It champions empirical observation over mental assumption as the more reliable path to truth, warning that confident thought is often the source of our deepest errors.
Relevance to William Harvey
Harvey spent decades dissecting hearts, measuring pulse rates, and calculating blood volume in living animals before concluding blood circulates continuously — overturning 1,400 years of Galenic doctrine. His entire method rested on trusting eyes over inherited texts: he watched venous valves prevent backflow and clocked how much blood the heart pumps per minute. This quote is his professional credo — direct observation corrects what the mind, steeped in authority, confidently gets wrong.
The era
Harvey worked during the Scientific Revolution, when Galileo, Bacon, and Vesalius were dismantling Aristotelian authority through experiment. Yet most European physicians still trusted Galen's ancient texts over dissection — his anatomical system had dominated medicine for fourteen centuries. Harvey published De Motu Cordis in 1628, facing fierce resistance from the medical establishment. The clash between bookish tradition and hands-on empiricism defined his age, making his insistence on watching over theorizing genuinely radical and professionally dangerous.
AI-generated insights based on extensive research and information for context. Factual errors? Email [email protected].