Here's a quote[1] from Adam Smith about the nature of effective taxes: "Good taxes meet four major criteria. They are (1) proportionate to incomes or abilities

Here's a quote[1] from Adam Smith about the nature of effective taxes: "Good taxes meet four major criteria. They are (1) proportionate to incomes or abilities to pay (2) certain rather than arbitrary (3) payable at times and in ways convenient to the taxpayers and (4) cheap to administer and collect." Is it profit or revenue that is taxed, generally? [1] - https://en.wikipedia.org/wiki/Theories_of_taxation https://en.wikipedia.org/wiki/Theories_of_taxation