Israeli President Shimon Peres’s annual conference in Jerusalem last week attracted political heavyweights such as Tony Blair and Henry Kissinger. The eminent assembly discussed the weighty issues of the day: Israeli social protests, American policy in the Middle East, the world economy going belly-up.

But it was one of the final sessions that has been a talking-point on social media: a master-class on “the future of sex” from Dr Ruth Westheimer.

A goodly crowd of VIPs heard the veteran psychotherapist deliver some reassuring information to any male who might have felt genitally short-changed: don’t worry, size really doesn’t matter…