What's the difference between modern democracy and classical democracy?

Classical democracy is direct democracy and modern democracy is representative democracy. Athenian democracy is a positive freedom. From the perspective of individual citizens, democracy is a kind of freedom, a kind of freedom of participation. Athenian democracy is an obligation of compulsory participation.

Modern democracy is a kind of negative freedom. Democracy is a political operation mode of "counting people without killing them". No matter how much the way and technology of "counting people's heads" are improved now, democracy also adheres to a preset, that is, even if the people are masters of their own affairs, they will never be a unified whole before any specific major issue, and will split into the majority and the minority. It also believes that the majority is unstable, the individuals that make up the majority are constantly changing, and the majority and the minority are always in mutual transformation. Citizens under modern democracy are "part-time political animals", and they have a broader "private life" besides their political life. They can choose to participate in political life or give up their right to speak in this field. No one can deny the existence of this "private sphere", interfere with citizens' choices, or force citizens to give up their lives in this field and become political animals, even in a democratic way-this just constitutes a restriction on democracy. Democracy's affirmation of this presupposition and difference reflects its negative and free character.

I hope it helps you.