What is act utilitarianism?

Act utilitarianism, founded by Jeremy Bentham, is a utilitarian view on ethics which holds that each person should act in a manner which brings about the greatest amount of happiness for the greatest number of people. The view was established on the basis of innate psychological hedonism; the idea that each person seeks pleasure and happiness as the ultimate life goal. Act utilitarianism operates by requiring the person to measure their actions against the 'hedonic calculus' (sometimes referred to as the felicific calculus) which is a theoretical list of conditions that the actor must assess his chosen act against in order to achieve the greatest amount of happiness for the greatest number. The hedonic calculus assesses the Act on the basis of its: Intensity: how strong and intense the pleasures arising from the act are. Duration: how long the pleasures arising from the act will last.Certainty: how likely it is that pleasure will occur upon the act being done. Propinquity: how soon the pleasure will occur once the act is done. Fecundity: the probability of the pleasures arising from the act being followed by other pleasures. Purity: the probability of the act bringing about unwanted sensations which are the opposite to pleasures and happiness. Extent: the amount of people the pleasures arising from the act will affect. The act which best satisfies this calculus will be deemed the most morally good under the act utilitarian view on ethics.