The basic intution behind utiltarianism is that we ought to bring about a world that contains as much happiness and as little unhappiness as possible.
Stated precisely, utilitarianism, in its arguably purest form (technically know as “scalar-act utilitarianism”), is the view that an action is better than another to the extent to which it leads to a greater balance of happiness (or, as it is sometimes called, well-being) over unhappiness (ill-being). Accordingly, utilitarians believe that in any given situation, the best action is the action that maximises the aggregate well-being.
Many people, when they first hear of utilitarianism, find it glaringly obvious that it is the true ethical theory.
Here is, for instance, how the philosopher Bertrand Russell describes his first encounter with utilitarianism:
It appeared to me obvious that the happiness of mankind should be the aim of all action, and I discovered to my surprise that there were those who thought otherwise. Belief in happiness, I found, was called Utilitarianism, and was merely one among a number of ethical theories. I adhered to it after this discovery.(1969)
Despite perhaps appearing obvious, utilitarianism has important practical consequences. In particular, it entails that it is tremendously important how we use i) our money, and ii) our time.
Wise use of our money is so important for utilitarians because there are charities out there that are incredibly cost-effective (i.e. that do incredible amounts of good for every dollar they receive), and we can bring about staggering amounts of happiness by donating a considerable proportion of our money to them. For instance, recent cost-effectiveness research suggests that donations to Against Malaria Foundation (which focuses on distributing insecticide-treated bednets to protect against mosquitoes that transmit malaria in developing world countries) allow one to save a life for under $2,000.(footnote: http://www.givewell.org/international/technical/programs/insecticide-treated-nets) Moreover, there are some causes that should arguably be even more important to utilitarians than those related to global poverty (see “Resources” (link)).
An organisation that aims to identify the most effective causes is Giving What We Can. Besides producing excellent research on charity cost-effectiveness, GWWC also provides a community of people who publicly pledge to give at least 10% of their income to the most cost-effective charities. (Such a commitment obviously makes a lot of sense from a utilitarian perspective, not only in order to make sure that we really follow through with our plans to donate a considerable proportion of our income, but also to send a credible signal that we will do so to others who are yet to be convinced.)
The second central issue for utilitarians is how to make best use of our time. As we will each typically spend around 80,000 (!) hours of our lives working, the central question in this area is clearly what career will allow us to do the most good.
80,000 Hours, a community that encourages people to make helping others as effectively as possible a significant part of their lives, looks into this question with great rigor.
Neither GWWC and 80k are specifically utilitarian organisations, but their objectives evidently align well with those of utilitarians.
Moreover, recent years have seen the growth of a now vibrant utilitarian community. If you are interested in getting involved, feel free to email email@example.com.