"Tis  better to be Socrates dissatisfied than a fool satisfied"John Stuart Mill
John Stuart Mill

John Stuart Mill was arguably the most important British philosopher of the 19th century. With an estimated IQ of 192, he was way ahead of his time in his advocacy of women's rights and his principle that we should be free to do what we like as long as it harms no-one else is still often quoted in many a modern debate.
For practical philosophy, he has 3 important ideas.
1) Consider the Consequences
Consequentialism is the idea that you base your decision-making on the consequences of your actions. Should you say the kind thing or the unkind thing? Should you give to charity or not? Should you continue to smoke or give up? If John Stuart Mill were here to advice you , he would say "consider the consequences". This is a very simple, forward-looking and helpful piece of advice- try it and see!
2) Value  happiness - both your own happiness and other people's happiness
Everyone wants happiness, and, Mill tells us, they are right to do so. Mill considered happiness to be the good, but his philosophy was more subtle than the old Epicurean ideal of just valuing pleasure. First, Mill and his fellow utilitarians thought that it is everyone's happiness that should be improved - not just your own. Try to make other people and yourself as happy as possible. Secondly, Mill did not think all pleasures equal - hence his famous "better Socrates dissatisfied than a fool satisfied" adage, This brings us to his third idea.
3) Ask "What would a well-informed person say and do in this situation?"
Mill disagreed with his godfather, Jeremy Bentham, that "pushpin was as good as poetry". He thought that any competent judge - someone who had experienced both - would prefer certain "higher" pleasures to "lower" ones. You don't have to agree with Mill about poetry to find value in his general idea - that we can benefit by asking "what would a well-informed person say about this situation?".  Wondering whether to become a teacher or a lawyer? Mill's idea suggests you should speak to someone who has experienced both - or better still, try out both yourself, before deciding.

External Links

Full text of Utilitarianism and Autobiography at www.utilitarianism.com
Prospect article for Mill bicentenary by Richard Reeves
Wiki article on J.S. Mill
Article in The Times to celebrate Mill bicentenary
Radio 4 "In our Times" on John Stuart Mill