In this week's episode, Laurie Taylor discusses progress with Professor Steven Pinker, the author of The Better Angels of Our Nature. Decline of Violence in History. Are we becoming less violent as a species?

Laurie also talks to Eric Anderson, a sociologist at Winchester University, who discusses his paper I Kiss Them Because I Love Them: The Emergence of Heterosexual Men Kissing in British Institutes of Education, which finds men more happy to kiss their friends than before.

This edition of Thinking Allowed was originally broadcast on BBC Radio 4 on Wednesday, 2nd November 2011. You can listen to the episode online on bbc.co.uk.

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