Even before Jeremy Bentham wrote his own treatise on utilitarianism, Enlightenment scholars were attempting to quantify a happy life. In the eighteenth century, Glasgow professor Francis Hutcheson offered an equation for benevolence, defined as the desire to spread happiness to others, where b = benevolence, a = ability, s = self-love, i = interest, and m = moment of good. His formula: ba = m + sa = m + i, and therefore b = (m + i)/a.