Answer:
The quote is by Irish historian and Politican James Bryce.
With the quote, Bryce is explaining that in democracy, citizens not only have political rights, but are also expected to engage actively in the political process: by voting for their representatives, by keeping an eye on public affairs, and so on.
At the same time, Bryce is saying that citizen dedication to democracy results in benefits for the people: the benefit of political freedom and civil liberties, and also the benefit of a better life made possible under this political system.
