Many things are clear without comparisons. For example, to accept that India is a democracy or that democratisation follows several stages needs no comparison of countries. In fact, you can spend a lot of interesting and fruitful time analysing the democratic characteristics and explanations of its success in India alone, so why make everything even more complicated by comparing it with other countries? What can be gained from comparisons?

In the first place, it widens and deepens our knowledge of the political world. A comparison of India and Canada would show not only that both countries are democratic but also that they are large federal systems with mixed ethnic and linguistic populations and that both were parts of the British Empire. Does one of these characteristics account, perhaps, for their democracy? To answer this question we need to compare the two with other countries. We might select Ghana, Nigeria and Pakistan, for example, and they would show that past membership of the British Empire is not a sufficient explanation of democratic development. We might select Denmark and Japan for our comparison and they would show that there is no necessary connection between federalism and democracy. And since Russia and China are both large and with mixed populations they would rule out the connection between large, heterogeneous populations and democracy.