Jack of all trades, master of none

"Jack of all trades, master of none" is a figure of speech used in reference to a person who has dabbled in many skills, rather than gaining expertise by focusing on one. An alternate phrasing says "Jack of all trades, master of none is oftentimes better than master of one."

The earliest recorded versions of the phrase do not contain the second clause. Indeed, they are broadly positive in tone. Such a Jack of all trades may be a master of integration, as such an individual knows enough from many learned trades and skills to be able to bring the individual's disciplines together in a practical manner. This person is a generalist rather than a specialist.

In Elizabethan English the quasi-New Latin term Johannes factotum ("Johnny do-it-all") was sometimes used, with the same negative connotation that "Jack of all trades" sometimes has today. The term was famously used by Robert Greene in his 1592 booklet Greene's Groats-Worth of Wit, in which he dismissively refers to actor-turned-playwright William Shakespeare with this term, the first published mention of the writer.

In 1612, the English-language version of the phrase appeared in the book "Essays and Characters of a Prison" by English writer Geffray Mynshul (Minshull), originally published in 1618, and probably based on the author's experience while held at Gray's Inn, London, when imprisoned for debt.

Mynshul uses only the first half of the phrase in the book, which may indicate that the phrase was in common usage at the time he wrote his account. Indeed, the "jack of all trades" part of the phrase was in common use during the 17th century and was generally used as a term of praise. "Jack" in those days was a generic term for "man."

The "master of none" element appears to have been added later; the expression ceased to be very flattering. Today, the phrase used in its entirety generally describes a person whose knowledge, while covering a number of areas, is superficial in all of them. When abbreviated as simply "jack of all trades," it is ambiguous; the user's intention is then dependent on context. In North America, the phrase has been in use since 1721, typically in its short form.

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