There’s no shortage of people claiming that the world cannot sustain population levels at the current size (just under 7 billion) much less a larger population. A common claim is that the planet’s resources will be consumed unsustainably, eventually leading to world starvation, famine, war, and population declines.
People are not cancer (most of them at least). Resources do not magically drop out of the sky like manna from heaven. For resources to be consumed, they must first be produced. Couple that with the fact that by any metric living standards (incomes, etc.) have been skyrocketing for almost two centuries and the simple conclusion is reached that each generation of human beings has access to more resources than the generations preceding them. To see why, consider how each of us consumes resources in our lifetimes. We must either be self-sufficient, which means we produce everything we need for ourselves. We can trade for resources. Or resources can be transferred to you. Transfers are most often accomplished through government actions, those that come from other mechanisms can still be characterized as I will characterize government transfers below, except for the fact that government actions are coercively applied.
In the self-sufficient case it is clear that there can be no depletion of resources and certainly no loss to others. In order for me to survive, I must produce resources for myself, and that production does not inflict losses on others (particularly when private property is respected and well defined). In the case of trading, the people surrendering resources to me are receiving something in exchange. So once again there is no net loss of resources (rather a gain). In the case of government redistribution, when resources are transferred to me, they must be taken from another individual. So my gain comes at the expense of others. Practiced on a large scale this transfer of resources will result in massive “over-consumption” of resources because those that are net recipients of resource transfers do not produce as many resources as they consume. And if opponents of this notion want to suggest that the coercion of productive individuals is only at the expense of the extra resources that those individuals have created, then they have contradicted the very premise behind their opposition to larger population and increased standards of living.
The overwhelming misunderstanding of those who think that our population is growing too large and that the high standards of living in the US are impoverishing the rest of the world is the false notion that if we reduced how much we consumed, or if we had never been born before, then suddenly more resources would be available for everyone else in the world. At best, everyone else would not be affected if you were not born, but the more likely outcome will be less for everyone, not more.