Social development was understood to be just another example of the unfolding universal laws of progressive development. This was a metaphysical principle that Spencer thought was repeatedly verified in phenomena as varied as embryological growth and the transition from primitive to civilized humans. Spencer coined the phrase survival of the fittest, and Darwin adopted the parlance in later editions of his Origin of Species. Darwin never extended the principle beyond the biological realm and remained wary of Spencer's speculative extrapolation into the sociological. Social Darwinism is really social Spencerism, but the fact that the idea has been misnamed has not made it any less powerful.
Nature unfolds in such a way that the strong survive and the weak perish.
It is better that capitalism has survived the Cold War, just as it was better that the mammals survived the Mesozoic era when dinosaurs became extinct. Because they survived, of course. This is not an evil tendency in business. It is merely the working out of a law of nature. These capitalist moguls eagerly embraced a metaphysics that provided the ultimate justification for their ruthless business tactics.