These words all denote various forms of brief expression of what are supposed to be accepted truths. A proverb is a homely illustration of a general truth and is couched and practical terms, as in "A fool and his money are soon parted." An adage is a time-honoured and widely known proverb, such as "Actions speak louder than words."

A maxim is a practical rule of conduct or action, such as, "Neither a borrower nor a lender be." The motto differs from the maxim in that it merely states a guiding principle or belief rather than a precept. Mottoes are usually chosen by a group, an institution, a nation, etc., as an expression of a purpose or ideal.

• "Be prepared" is the motto of the Boy Scouts; "In God we trust" is the motto of the United States.

A saying is a figure of speech or a remark of any type that is current among ordinary people. Sayings are repeated often, sometimes to the point of losing their freshness.

• As the saying goes, "He has bats in the belfry", As I always say, "Live and let live."

Saying also has the general meaning of any noteworthy or pungent observation, especially one of a group culled from the writings and speeches of well-known figures. One speaks of the saying of Marcus Aurelius or the sayings of Confucius.

The remaining words all refer to expressions that are more consciously literary or clever than are proverbs and adages ; furthermore, their authorship is more often known. An epigram is a brief, pointed remark in verse, prose or conversation that expresses a witty or even satirical observation. "The only way to get rid of a temptation is to yield to it," wrote Oscar Wilde, a composer of brilliant epigrams . Epigraphs is sometimes confused with epigram , but it refers strictly to a brief quotations, rich in implications, that introduces a piece of writing: Eliot used a quotation from Conrad as an epigraph to his poem "The Hollow Men." Less commonly now, the word can refer also to the inscription of a motto in some material such as store or metal: the epigraph on the coin. Epitaph , often confused with epigram and epigraph , refers to a verse or prose inscription on a tombstone, or, more generally, to any phrase by which someone is remembered after death. Whether signed or anonymous, an epitaph may be composed for the occasion or consist of a quoted adage or motto: a hobby of collecting colourful epitaphs to be found in old graveyards.

An aphorism is a thought-provoking remark that does not yield all its meaning so readily as an epigram and aims at profundity rather than wit. An aphorism may be embedded in a longer work, as the following observation from King Lear: "As flies to wanton boys are we to the gods; they kill us for their sport." In other cases, authors have deliberately written groups, sequences or even books of aphorisms : the aphorisms of Kafka. An apothegm is a startling or paradoxical assertion, such as Swift’s remark. "There is nothing in this world constant but inconstancy."