Suppose Malthus were right. What would you see looking back over a 2 million year period? You wouldn't see 40 trillion people alive today. You'd see repeated cycles of boom-bust: Population growth, overpopulation, population crash.

And this is not what we see! Please take note of the Hanson quote in my original.

If you could state how the observation would differ if Malthus were wrong vs. if Malthus were right, I might listen to you.

If Malthus were wrong, we could expect to see any number of things that don't involve growth-overpopulation-crash cycles. For example, we might see slow and steady population growth with very irregular population crashes which correspond with major natural disasters (which are responsible for sudden, large, discontinuous declines in the available food supply). In this particular scenario, we would expect to see very few human fossils that show signs of malnutrition. Whereas if Malthus had been right, we would expect to see much more fluctuation in population levels, and therefore a proportionally high number of human fossils with signs of malnutrition, because deadly famines would be proportionally more common.

And whether or not JanetK thinks I am naive, archaeologists have not found very many malnourished human fossils. Furthermore, if Malthus had been right, we should expect to see most modern forager tribes having at least occasional difficulties getting enough to eat. We should likewise see heavy fluctuation of prey animal populations in the vicinity of human hunter-gatherers.

The Lotka-Volterra equation may do a wonderful job of explaining simple predator-prey relationships, but it assumes exponential growth of the prey population, which is exactly what I'm disputing. [ETA: I took a closer look at the Wikipedia page and noticed that the LV equation also assumes that "the prey population finds ample food at all times." Removing predators from this equation doesn't give you Malthus. It gives you infinite growth forever.]

The way Malthus was wrong was in not observing that viruses and pathogenic bacteria are predators of humans.

Disease epidemics as we currently imagine them did not exist pre-agriculture. Small, widely-dispersed human populations can't support a sustainable population of bacteria or viruses. The rate of transmission is too low.