Utilitarianism is based around the Principle of Utility - greatest good for the greatest number.
Success - More people are taken into account (greatest number)
Failure - Minority are not considered when using the Principle of Utility
Bentham was a Hedonist and pleasure seeker. His argument was telelogical - taking the consequence into account.
He believed in the greatest pleasure for the greatest number.
However, this means that any act may be allowed or justified.
When measuring pleasure, Bentham uses the Hedonic Calculus. A way to remember this is;
R - Richness
E - Extent
D - Duration
P - Purity
R - Remoteness
I - Intensity
C - Certainty
Bentham was Act. This means that in every situation, he would apply the Principle of Utility. Therefore, he takes every situation into account. However, you cannot predict the consequence of a decision being made, how long will the pleasure remain?
Benthams argument is strong. Because in every situation he would add the Principle of Utility, meaning it was flexible.
Mill was a son of a follower of Bentham. He therefore studied Benthams views and opinions.
He agreed with the Principle of Utility, however, instead of greatest pleasure for the greastest number, Mill said the greatest happiness for the greatest pleasure.
He believed that you cannot measure pleasure.
A quote which Mill used was 'It is better to be a man disatisfied than a pig satisfied, and it is better to be Socrates disatisfied than a fool satisfied.'
Mill broke the Hedonic Calculus into higher and lower pleasures. Higher pleasure were things to do with the mind, such as reading, writing etc. Lower pleasures were to do with the body, sex, food, drink etc. We need both higher and lower pleasure to survive. We cannot live without thinking, reading etc, and we cannot live without food and water.
Mill was Rule. This means that the rules of society are based around the Principle of Utility, such as 'do not kill, do not steal' etc. It's easy to apply, as we've added the rule. It focuses on the greatness of society.
Mill's argument was weak. If we get into a situation where consequences are harmful, we can break the Principle of Utility - going against the Principle of Utility completely!
Peter Singer wanted to minimise pain rather than maximising pleasure.
He believed that Act and Rule overlooked the minority.
In every situation, he'd weigh up the preferences, based on what minimises the most pain. This would maximise the chances that everyone's preferences would be satisfied.
However, preferences might clash!
Peter Singer took animals into account unlike Bentham and Mill. He looked at the preference of the animal. Bentham and Mill believed that Humans were more dominant that animals.
Singer's argument is more empathetic - considered everything.
What is good is preference satisfaction.
Our preferences are equal, we must weigh them up.
However, there is difficulty in accuracy of preference.
Objective - Without being biased.
Subjective - Personal opinion, not fixed rules.