The chair of the Philosophy Department of Yeshiva University, James Otteson, has a piece published by the Manhattan Institute on "The Moral Case for Capitalism." It takes the long view:
Since 1800, the world's population has increased sixfold; yet despite this enormous increase, real income per person has increased approximately 16-fold. That is a truly amazing achievement. In America, the increase is even more dramatic: in 1800, the total population in America was 5.3 million, life expectancy was 39, and the real gross domestic product per capita was $1,343 (in 2010 dollars); in 2011, our population was 308 million, our life expectancy was 78, and our GDP per capita was $48,800. Thus even while the population increased 58-fold, our life expectancy doubled, and our GDP per capita increased almost 36-fold. Such growth is unprecedented in the history of humankind. Considering that worldwide per-capita real income for the previous 99.9 percent of human existence averaged consistently around $1 per day, that is extraordinary. What explains it? It would seem that it is due principally to the complex of institutions usually included under the term "capitalism," since the main thing that changed between 200 years ago and the previous 100,000 years of human history was the introduction and embrace of so-called capitalist institutions—particularly, private property and markets.
It's a lovely article. I would add, though, that private property and markets did exist earlier than 200 years ago, as two of the Ten Commandments — "thou shalt not steal" and "thou shalt not covet thy neighbor's house" — make clear. It would also be interesting to examine some of the alternative explanations for the boom since 1800 — democracy, technology — side by side against the capitalist explanation.