Effective Altruism (EA) is a movement trying to invest time and money in causes that do the most good per some unit of effort. The label applies broadly, including a philosophy, a community, a set of organisations and set of behaviours. Likewise it also sometimes means how to donate effectively to charities, choose one's career, do the most good per $, do good in general or ensure the most good happens. All of these different framings have slightly different implications.

The basic concept behind EA is that one would really struggle to donate 100 times more money or time to charity than you currently do but, spending a little time researching who to donate to could have an impact on roughly this order of magnitude. The same argument works for doing good with your career or volunteer hours.

The Effective Altruism movement also has its own forum, The EA Forum. It runs on the same software as LessWrong.

Key Concepts

The Scale, Neglectedness, Tractability, (Personal Fit) criteria

Despite a broad diversity of ideas within the EA community on which areas are most pressing, there are a handful of criteria that are generally agreed make an area potentially impactful to work on (either directly or through donation). These are:

The area has the potential for impact at scale, either in human lives saved, animal or human suffering alleviated, catastrophic crises averted, etc. Sometimes this is called "importance"
The area is generally neglected, that is, it has capacity for more support either financially or in terms of skills. An area with lots of resources should lead us to think we are less likely to be able to make improvements.
The area is tractable, it is a solvable problem, or is solvable with minimal resource investment (relative to other problem areas)

A fourth semi-area is:

Does the individual have good personal fit? Do they have unique skills which will make them more effective in an area.

Impartiality (geographic, species, time)

Global health and wellbeing (geographic impartiality)

One morning, I say to them, you notice a child has fallen in and appears to be drowning. To wade in and pull the child out would be easy but it will mean that you get your clothes wet and muddy, and by the time you go home and change you will have missed your first class.
I then ask the students: do you have any obligation to rescue the child? Unanimously, the

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