Full Idea
There is only one good, namely knowledge, and there is only one evil, namely ignorance.
Gist of Idea
The only good is knowledge, and the only evil is ignorance
Source
report of Socrates (reports of career [c.420 BCE]) by Diogenes Laertius - Lives of Eminent Philosophers 02.4.14
Book Reference
Diogenes Laertius: 'Diogenes Laertius', ed/tr. Yonge,C.D. [Henry G. Bohn 1853], p.68
A Reaction
Ignorance of how to commit evil sounds quite good.