Philip Plait > Quotes > Quote > Manish liked it

“I am using the word theory as a scientist means it: a set of ideas so well established by observations and physical models that it is essentially indistinguishable from fact. That is different from the colloquial use that means "guess." To a scientist, you can bet your life on a theory. Remember, gravity is "just a theory" too.”
― Philip C. Plait, Death from the Skies!: These Are the Ways the World Will End...