An aphorism (from Greek ἀφορισμός: aphorismos, denoting 'delimitation', 'distinction', and 'definition') is a concise, terse, laconic, or memorable expression of a general truth or principle. Aphorisms are often handed down by tradition from generation to generation.
The concept is generally distinct from those of an adage, brocard, chiasmus, epigram, maxim (legal or philosophical), principle, proverb, and saying; although some of these concepts may be construed as types of aphorism.
Often, aphorisms are distinguished from other short sayings by the need for interpretation to make sense of them. In A Theory of the Aphorism, Andrew Hui defined an aphorism as "a short saying that requires interpretation".
A famous example is:
It is not possible to step into the same river twice.
The word was first used in the Aphorisms of Hippocrates, a long series of propositions concerning the symptoms and diagnosis of disease and the art of healing and medicine. The often cited first sentence of this work is: "Ὁ βίος βραχύς, δὲ τέχνη μακρή" - "life is short, art is long", usually reversed in order (see Ars longa, vita brevis).
This aphorism was later applied or adapted to physical science and then morphed into multifarious aphorisms of philosophy, morality, and literature. Currently an aphorism is generally understood to be a concise and eloquent statement of truth.
Aphorisms are distinct from axioms: aphorisms generally originate from experience and custom, whereas axioms are self-evident truths and therefore require no additional proof. Aphorisms have been especially used in subjects to which no methodical or scientific treatment was originally applied, such as agriculture, medicine, jurisprudence and politics.
Aphoristic collections, sometimes known as wisdom literature, have a prominent place in the canons of several ancient societies, such as the Sutra literature of India, the Biblical Ecclesiastes, Islamic hadiths, the golden verses of Pythagoras, Hesiod's Works and Days, the Delphic maxims, and Epictetus' Handbook.