Surprisingly, perhaps, given how important it is to the rest of us, philosophers haven't tended to talk much about love.
An honourable exception was the German philosopher Arthur Schopenhauer, who believed that love was the most important thing in life.
Alain shows how the ideals of a man he calls 'philosophy's Dr Love' explain the mystery of why we fall in love with the people we do.
He believes that Schopenhauer's philosophy is particularly consoling to anyone who's been rejected, and he talks it over with Michele Hutchinson, whose boyfriend recently jilted her.
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