How do we differentiate a moderate person from a left/right extremist?

[Patrick]

The conflict isn't between the left and right wing, it's between liberty and tyranny. And both Republicans and Democrats are the tyrants, whether they want to admit it or not.

[RockHunter]

Left or Right...those labels are too generic to be really useful. They cover too many subjects.
One can be right of left on social or economic or hundreds of other subjects, and most people only accumulate various leanings rather than steer to one OR the other.

I find that those who whine the loudest about someone else being the extremist, is actually the extremist himself. When one side claims to be "moderate" or "center" yet uses terms like "far-left/right" or "extremist", that says a lot about the character and integrity of that side.

[immenseday266]

If they have beliefs similar to communism, then they are left wing extremists.
If they have beliefs similar to fascism, then they are right wing extremists.