“I could not understand why men who knew all about good and evil could hate and kill each other.”
Source: Frankenstein
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Mary Wollstonecraft Shelley 94
English novelist, short story writer, dramatist, essayist, … 1797–1851Related quotes

Dennis Prager, Speaking at the 20th Anniversary Gala of the Freedom Center https://www.youtube.com/watch?v=4pCAhVStBIY (2 February 2008), retrieved 26 August 2015
2000s

“If men could only know each other, they would never either idolize or hate.”
Source: A Thousand & One Epigrams: Selected from the Writings of Elbert Hubbard (1911), p. 13.

On Sunnis and Shia, as quoted in CNN http://www.cnn.com/POLITICS/blogs/politicalticker/2006/09/lott-bush-barely-mentioned-iraq-in.html (2006).
2000s

On the same-sex marriage controversy in the Church of England.
"Tony Benn: The glorious revolutionary" http://www.journal-online.co.uk/article/3082-tony-benn-the-glorious-revolutionary, The Journal (26 March 2008).
2000s

Source: The Beach (1941), Chapter 3, p. 20