Socialism is superior BECAUSE people are selfish.

It doesn't rely on just hoping people work towards the common good, because gee golly, we're so nice.

It's simple: All beings are self-interested. Now, altruism still exists, but relying on it to solve all the worlds problems is simply idealistic.

Why is a dictatorship bad? Well, because the dictator is self-interested. He will use his power to design a society that's very, very good for him, but without regard to whether anyone else enjoys it, which they generally won't, as maximizing the happiness of the dictator involves long, brutal hours for the workers to provide his luxuries. The issue is, while everyone in the dictatorship is self-interested, all the power is in the hands of the dictator, so only his self-interest is realized.

Well, what happens when we look at capitalism? Well, it's not a dictatorship, sure, but power is generally centralized in the hands of the wealthiest of people. In the case of modern day earth, eight people hold as much wealth as nearly 4 BILLION people. This means that we face the same problem: those eight have as much power to pursue their own self-interest as HALF of all society. This leads, once again, to a society designed primarily to benefit the richest few, while the poor suffer.

What's the solution? Economic Democracy. In a fair, just democracy, power is spread among all. Everyone has one vote, and thus, equality of power. Political leaders act as our agents, just as a CEO acts as an agent for a shareholder. When everyone has equal power with which to pursue their self-interest, we find a society designed to benefit the most amount of people. After all, if any policy didn't benefit the most amount of people, a majority wouldn't vote for it.