"utterance, recitation, act of the verb 'say,' " c.1300, prp. of say (v.); meaning "something that has been said" (usually by someone thought important) is from c.1300; sense of "a proverb" is first attested mid-15c.
Be self-evident, a matter of course. For example, It goes without saying that success is the product of hard work. This expression is a translation of the French cela va sans dire. [Second half of 1800s]