If At First You Don't Succeed....
What might happen if a people believed (a) it is possible to build a utopian society; and (b) there is no transcendent source of ethical behavior? Well, then, I guess anything goes, right? Whatever works. Pragmatism.
People really did believe that it was possible to build this grand utopian society. In fact, I do not think it was simply blind rage that fueled the reign of terror in France. Nor do I think it was just political, economic and social factors (although they certainly contributed). Underneath it all was the idea that wrong-thinking people were gumming up the works and should be eliminated.
After all, we're talking about building a perfect world here. Can't make an omelete without breaking a few eggs. There's going to be a certain amount of collateral damage in anything like this.
Of course, the French Revolution was a disaster, and that took the wind out of the sails of Enlightenment optimism...for a while.
But, with the scientific method as their guide, many realized that this was simply one failure. Trial and error would eventually show us the right way. Let's just tinker with the factors and try the experiment again.
But what should the next experiment look like? Should we take a more gradual approach? Or should we use more brute force? Should we use long and slow education or quick and blunt power?
See, without some transcendent guide, even if you can get everyone to agree on where we should go, there will always be serious disagreement about how we should get there.
As you think through the history of the last few centuries, what are some of the ways people have tried to bring about heaven on earth?