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. Inversely, a common modern meaning is that a person must stay active to avoid stagnation.

In English

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 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 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 the 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.

Accuracy

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.

In psychiatry

Because it is so well known, this saying is one of the most common proverbs used in psychological tests for mental illness, particularly schizophrenia, to look for difficulty with abstraction. American research conducted in the 1950s between Air Force basic airmen and hospitalized Veterans Administration patients with schizophrenia found that the way a person interprets proverbs can be used to determine abstraction ability. The lack of abstraction ability in these studies was statistically significantly higher in the VA patients and it has thus been construed as indicating pathology. As persons with mental illness are generally believed to demonstrate "concrete" thinking the research results have, in practice, often been improperly generalized to suggest proverbs alone can be a sufficient indicator of mental illness.
A "concrete" interpretation of the proverb "a rolling stone gathers no moss" would simply restate the proverb in different words, rather than delivering any metaphorical meaning.

Cultural references

In comics