It's in the mix

Thomas Malthus predicted that we’ve have the fourt horsemen of the Apocalypse on our doorstep due to geometric rise in population levels, but arithmetic rise in our capacity to support ourselves.

This has not yet come to pass. Why not?

Some say that the more people you have the more ideas there will be, and it is those ideas that are saving us.
Others, amongst which I number myself, would argue that there are two processes going on:

1. Necessity is the mother of invention, and since mankind only really leaps ahead when we have to, we have kept pace with the demands made upon us
2. More importantly it is the MIX of ideas across the planet and the sharing of best practises that have allowed this to happen.

The number of people argument is a little too close to the “every abortion is a potential Einstein” school of thinking, which is a bit beneath the rational mind.