What is living on interest?

Question

environmentally what is living on principal and living on interest?

Answer 1

An analogy is being made between how we (collectively) are treating the environment, and how an individual person may treat his wealth.

An independently wealthy person may be able to live entirely off of the interest of his investments (or, more realistically, off of some of the earnings of his investments).  If he can do this, then his wealth never decreases, because he is preserving the "engine" that is making the money.  Otherwise, he may be tapping into his savings (the "principal").  But by decreasing the principal, he is destroying the engine that provides interest.

We (collectively) are rapidly using up our stores of fossil fuels.  This is similar to tapping into the "principal".  If we switched entirely to only renewable energy sources, it would be more similar to living on the interest only.

Answer 2

Environmentally, I would think it means to live off of what is already planted/ living instead of consuming and replanting/ rebreeding. I dunno tho!