Historical clue formulations

• The "vice of narrow souls," per Balzac — 2021-10-17
• "___ is gained as much by good works as by evil": Machiavelli — 2019-02-01
• It "paralyzes life," per Martin Luther King Jr. — 2017-01-14
• "A sentiment appropriate to the occasion of another's superiority," per Ambrose Bierce — 2015-02-06
• Extreme aversion — 2013-02-24
• Enmity — 2012-03-28
• "___ is gained as much by good works as by evil": Machiavelli — 2009-08-12
• Odium — 2009-01-04
• It's "heavier freight for the shipper than it is for the consignee": Augustus Thomas — 2007-10-20
• Churchill called it "soul-destroying" — 2001-10-24
• Cause of some warfare — 2001-05-02
• "___ stirreth up strifes": Proverbs — 1999-05-23