Cause "according to the criterion of others' welfare" doesn't require "at ones own expense".
I do not see the contradiction. Could you elaborate?
I added Eliezer's definition of "altruist" to the page, which contradicts the current definition, which I think is wrong and should be removed. Thoughts?
"an "altruist" is someone who chooses between actions according to the criterion of others' welfare" - Eliezer Yudkowsky
Sure, but it does not preclude it. Moreover, if the costs of the actions are not borne by the altruist (e.g. by defrauding customers, or extortion), I would not consider it altruism.
In this sense, altruism is a categorization tag placed on actions.
I do see how you might add a second, deontological definition ('a belief system held by altruists'), but I wouldn't. From the post, "Humane" or "Inner Goodness" seem more apt in exploring these ideas.