What is the significance of utilitarianism?: originally appeared on Quora: The best answer to any question. Ask a question, get a great answer. Learn from experts and access insider knowledge. You can follow Quora on Twitter, Facebook, and Google+.
Utilitarianism says that we should always do what will have the best consequences for all those affected by our actions. "Best consequences" generally refers to well-being, in some sense, although utilitarians differ on whether this means happiness, and the reduction of suffering, or something like the satisfaction of preferences.
Utilitarians don't just focus on their friends or family, or their fellow-citizens. They are concerned about distant strangers. They are concerned about future generations (so utilitarianism tells us why climate change matters, for example, even if its most severe effects won't be felt for another century). And "all affected" includes all sentient beings, so the suffering of animals matters too.
That's a clear and straightforward ethical position. Virtually everyone agrees that it's better for sentient beings to be happier and have less suffering. That's not enough to make everyone a utilitarian, because some people think that in addition, there are absolute moral rules one must never break. Most moral rules are useful guides to what will bring about the best consequences. But if they are not -- if we really know, with certainty, that obeying a moral rule will have worse consequences than breaking it -- should we still obey it? Why? That's the challenge utilitarianism poses to other views.
Utilitarianism changes people's lives in many ways. For example it leads many people to support Effective Altruism, a growing movement of people who want to be as effective as possible in making the world a better place. They want to do (advert warning, this is the title of my forthcoming book) The Most Good You Can Do. That doesn't mean that all EAs are utilitarians, but utilitarians are, or ought to be, EAs.
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