4. What is the difference between a radical and a moderate?

Explanation:

In general terms, a radical is one who wants “root and branch” change (Latin: Radix, a root), based on the sense of certainty that a set of principles should be applied, principles that run counter to those involved in the status quo.

Its true opposite is conservative. A classic conservative is very wary of drastic change based on a set of a priori principles, because given the fallen state of man, and the fallibility of human reason, it is better to retain at least those elements of things as they are that are sort of working. Given the horrors released by many revolutions, there is a lot of empirical evidence to support this view.