For the case of resource exhaustion Carden points to the work of Julian Simon on why we shouldn't worry about running out of things. Carden notes,
Simon (and those who have come after him) have been derided for having a blind “faith” in technology, but Simon is more careful than he gets credit for being. If demand for resources rises, prices of resources will rise in the short run. This will give people incentives to search for more of those resources or develop substitutes. We don’t just “get lucky” with technology. Rather, we have the conditions under which people have powerful incentives to solve seemingly intractable problems. When people have those powerful incentives—the incentives provided by private property and free markets—we don’t need to worry about whether we will run out of anything.So what about overpopulation? Carden continues,
What, then, should be done to restrain population growth? I think the answer is easy even though it offends our biases toward action and our conceit: nothing. Ebenezer Scrooge cruelly and callously dismissed “the surplus population,” but as I argued in 2010, there is no such thing. If anything, we don’t need fewer people. We need more of them. Why is this? Every person brings something unique and precious into the world: a mind. It is this mind that he or she uses to solve problems, to come up with newer and better ways to remove what the economist Ludwig von Mises called “felt uneasiness,” to conceive of and create feats of engineering or artwork that boggle the mind. As a lot of people before me have done, I ask you to consider people who are the kinds of one-in-a-million game-changers who rewrite history. With a billion more people, we would have another thousand such geniuses.So don't worry, be happy.
Nonetheless, there are billions of people who still live in dire poverty around the world; indeed, by the one-in-a-million math, for the two-and-a-half billion or so people in the world who live on less than $2 per day, it means that there are about 2500 one-in-a-million geniuses who are denied the opportunity to live to their full potential because of an accident of birth. Why are they poor? It isn’t because there are a lot of them. It’s because, for the most part, they live in countries that lack economic freedom and what Deirdre McCloskey calls Bourgeois Dignity.
The solution to world poverty and resource constraints most certainly isn’t “fewer people.” The solution is to create opportunities for the world’s poor through the institutions and attitudes that are responsible for the explosion of wealth we have seen in the last few centuries in the western world: secure private property rights, free markets, and dignity for entrepreneurs and innovators.