Who said all it takes for evil to win is for enough good men to do nothing?

Answer 1

Edmund Burke. The actual quote is: "The only thing necessary for the triumph [of evil] is for good men to do nothing."

Addendum:

The "actual quote" cannot be found. While it is attributed to Burke, there is not evidence that he ever actually spoke or wrote it, and Burke was a prolific writer and speaker.

There have been countless attempts to tie it to a specific piece of writing, and some of these are laudable. One of the most likely sources of this particular bit of wisdom could be: When bad men combine, the good must associate; else they will fall one by one, an unpitied sacrifice in a contemptible struggle. It was born in Burke's speech of 23 April 1770, "Thoughts on the Cause of the Present Discontents," delivered to the House of Commons.

The quote as it is in the question appears in at least eleven different permutations on the internet:

1. The only thing necessary for the triumph of evil is for good men to do nothing.
2. All that is needed for the forces of evil to triumph is for enough good men to do nothing.
3. All that is required for evil to prevail is for good men to do nothing.
4. In order for 'evil' to prevail, all that need happen is for 'good' people to do nothing.
5. All that is needed for evil to prevail is for good men to do nothing.
6. The surest way for evil to prevail is for good men to do nothing.
7. All it will take for evil to prevail is for good people to do nothing.
8. All that is necessary for the forces of evil to take root in the world is for enough good men to do nothing.
9. All that is needed for the forces of evil to succeed is for enough good men to remain silent.
10. All it takes for Evil to prevail in this world is for enough good men to do nothing.
11. The only thing necessary for the triumph of evil is for good men to do nothing.

These more commonly worded permutations of Burke's message survive, perhaps more because they appeal to the modern ear. Call it poetic license, but Burke's words live on, they just look a little different.

Answer 2

Thomas Jefferson