What does mathematics have to do with poetry? Seemingly, nothing. Mathematics deals with abstractions while poetry with emotions. And yet, the two share something essential: Beauty. “Euclid alone has looked on beauty bare,” says the title of a poem by Edna St. Vincent Millay. “Mathematics, Poetry and Beauty” tries to solve the secret of the similarity between the two domains. It tries to explain how a mathematical argument and a poem can move us in the same way. Mathematical and poetic techniques are compared, with the aim of showing how they evoke the same sense of beauty. The reader may find that, as Bertrand Russell said, “Mathematics, rightly viewed, possesses not only truth, but supreme beauty - a beauty hold and austere, like that of sculpture . . . sublimely pure, and capable of a stern perfection such as only the greatest art can show.”