I think parent's point is that the "progress of society" is subjective and not necessarily absolutely "good" or "evil". The Aztecs were technologically very advanced to the benefit of their people, but ritually practiced vast human sacrifice.

The progress is also not necessarily linear; Oscar Wilde would've no doubt preferred ancient Greece to his own time, about 2000 years later, when it comes to their attitude toward social progression. The sciences, by contrast, do tend to show unequivocal progress because they're essentially our growing understanding of the universe.