What is the philosophical case for democracy?

Why should I care about any particular political ideology (conservatism, liberalism, communism, anarchism), and why would I think any one of them is better than the others?<br><br>What's the historical philosophical argument for democracy over all other forms of governance? Democracy is a measurable and practical way to run a society, but why is democracy better than other forms of governance?<br><br>Why should I place any value on democracy?