The notion of matter has enjoyed an almost unparalleled development in the history of Western thought. It was introduced by Aristotle as a principle of low ontological status and became prominent already with the Stoics. It was definitively elevated to the rank of substance by the 17th century founders of modern thought. The 19th and aoth century "materialists", then, in agreement with most thinkers of the French Enlightenment, even considered matter to be the only reality that truly exists.