Singer makes a direct appeal to the universal moral principles of utilitarianism -- equality, impartiality, and universality -- by outlining degrees of pleasure and pain, and utilising a form of felicific calculus
. He calculates what is morally right by weighing the relative pains and pleasures of everyone equally and defines morality as an action that amplifies social utility.
Bentham's felicific calculus
, that policy should be concerned with the greatest happiness of the greatest number, gradually confined beauty to a preserve of elites.
With Bentham and the felicific calculus
? Was Walras, as Schumpeter wrote, the greatest economist who ever lived, at least that is until his twentieth century successors, Arrow and Debreu and McKenzie, surpassed him?
Its value and importance cannot be determined by the felicific calculus
, for you cannot calculate the searing insight which comes from, say, Primo Levi's account of his life in a concentration camp, If This Is a Man (1958).