A rolling stone gathers no moss

A rolling stone gathers no moss is an old proverb, credited to Publilius Syrus, who in his Sententiae states, People who are always moving, with no roots in one place or another, avoid responsibilities and cares. As such, the proverb is often interpreted as referring to figurative nomads who avoid taking on responsibilities or cultivating or advancing their own knowledge, experience, or culture. Another interpretation equates "moss" to ""; as such the proverb can also refer to those who keep moving as never lacking for fresh ideas or creativity.

The conventional English translation appeared in John Heywood's collection of Proverbs in 1546. Brewer's Dictionary of Phrase and Fable also credits Erasmus, and relates it to other Latin proverbs, Planta quae saepius transfertus non coalescit, or Saepius plantata arbor fructum profert exiguum, which mean that a frequently replanted plant or tree (respectively) yields little fruit. It appears that the original intent of the proverb saw the growth of moss as desirable, and that the intent was to condemn mobility as unprofitable.

The contemporary interpretation of equating moss to undesirable stagnation has turned the traditional understanding on its head. Erasmus's proverb gave the name "rolling stone" to people who are agile (mobile) and never get rusty due to constant motion.

"A day in the moss" refers to cutting peat in bogs or mosses. Metaphorically this refers to hard work in preparation for winter. An itinerant "rolling stone" will not likely feel the timely need to apply for access to a community's peat bog.

The saying may not be authentic to Syrus; the Latin form usually given, Saxum volutum non obducitur musco, does not appear in the edited texts of Publilius Syrus. It does, however, appear with similar wording in Erasmus' Adagia, which was first published around 1500. It is also given as "Musco lapis volutus haud obducitur", and in some cases as "Musco lapis volutus haud obvolvitur".

The literal meaning of the statement itself is true. The television show MythBusters showed that after six months of constantly rolling a stone does not grow moss.

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