From my position of relative affluence though, it'd seem selfish to only vote in my own interest. I have the luxury of being able to afford to consider the best interests of others, so by default I think I should. In effect, my vote is something I can give away to help people less fortunate than I am.
However, I'm not sure that I can ethically do that. If I make a choice on behalf of others, there's a real risk that I get it wrong, which would in some ways be worse than not considering the "others" at all. Through a lack of understanding I may have unwittingly overridden the wishes of the people who were trying to get what they knew was best for themselves. Even if one decides that the best idea is for people to be able to determine their own outcomes, voting to enable might be worse than voting for the right sort of benevolent dictator to impose the best possible solution (the classic liberal vs socialist dichotomy).
Is voting just in my own interest selfish? Is voting in what I consider to be the interests of other people illiberal, paternalistic and patronising?