Rhetoric versus demonstration

rhetoric encourages readers to assume that words are proof.

It can.

For example:

"History always moves toward justice."

This sounds powerful.

But by itself it proves nothing.

To become a demonstration, the author would need to show evidence and reasoning establishing that conclusion.

So when I say

"Life moves forward"

is rhetorical,

I meant it expresses a viewpoint vividly but does not itself demonstrate that present claims should always outweigh ancient ones.

A demonstration is not simply something that "has occurred." In argumentation, a demonstration is a reasoned proof: a conclusion supported by evidence and logical steps. Rhetorical phrases can make an argument memorable, but they cannot replace those supporting steps.