a little knowledge is a dangerous thing

English

A slight misquotation of Alexander Pope’s a little learning is a dangerous thing. The earliest use dates from a magazine published in 1774.^[1]

A limited understanding of a subject can lead individuals to overestimate their expertise, often resulting in errors or misguided decisions due to false confidence.
Synonym: a little learning is a dangerous thing
- 1926, Francis Blake Atkinson, Hallam Hawksworth, A Year in the Wonderland of Trees, page 176:
  Of course anybody can saw off a limb; but here, as so often happens, a little knowledge is a dangerous thing, and a little more will often save a dear old friend of the family and the neighborhood.

^ Gary Martin (1997–), “A little knowledge is a dangerous thing”, in The Phrase Finder, retrieved 26 February 2017.