That action is best which procures the greatest happiness.
To be a utilitarian means that you judge actions as right or wrong in accordance with whether they have good consequences. So you try to do what will have the best consequences for all of those affected.
Utilitarianism is a philosophy from the olden days exploring the idea that whatever is best for the majority is the fairest.
Priestly was the first (unless it was Becarria) who taught my lips to pronounce this sacred truth--that the greatest happiness of the greatest number is the foundation of morals and legislation.
It was the mystical dogma of Bentham and Adam Smith and the rest, that some of the worst of human passions would turn out to be all for the best. It was the mysterious doctrine that selfishness would do the work of unselfishness.
It is the greatest good to the greatest number which is the measure of right and wrong.
To what shall the character of utility be ascribed, if not to that which is a source of pleasure?
This, and no other, is justice: — to consider, under all the circumstances and consequences of a particular case, how the greatest quantity and purest quality of happiness will ensue from any action ... there is no other justice.
The nineteenth century, utilitarian throughout, set up a utilitarian interpretation of the phenomenon of life which has come down to us and may still be considered as the commonplace of everyday thinking. ... An innate blindness seems to have closed the eyes of this epoch to all but those facts which show life as a phenomenon of utility
