Why is Plato and greek government different?

Plato was a Greek philosopher that died thousands of years ago. The Greek government died only recently.

That is a good punchline, but the Greek government in Plato's time was a true Democracy; everyone was expected to be a part of the decision making body once a year, for a month. Plato did not believe in Democracy because he felt the average person was incapable of making good decisions. He preferred rule by the intelligent; philosophers.