Who wrote Our constitution is called a democracy because power is in the hands not of a minority but of the whole people?

This quote is from Pericles' Funeral Oration, c.490 BCE from Thucydides, The Peloponnesian War.

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Let me say that our system of government does not copy the institutions of our neighbours. It is more the case of our being a model to others, than of our imitating anyone else. Our constitution is called a democracy because power is in the hands not of a minority but of the whole people. When it is a question of settling private disputes, everyone is equal before the law; when it is a question of putting one person before another in positions of public responsibility, what counts is not membership of a particular class, but the actual ability which the man possess. No one, so long as he has it in him to be of service to the state, is kept in political obscurity because of poverty. And, just as our political life is free and open, so is our day-to-day life in our relations with each other. We do not get into a state with our next-door neighbour if he enjoys himself in his own way, nor do we give him the kind of black looks which, though they do no real harm, still do hurt people's feelings. We are free and tolerant in our private lives; but in public affairs we keep the law. This is because it commands our deep respect.