There is a peculiar attitude, here at the beginning of the 21st century. On the one hand, we agree things aren’t fine. On the other hand, there’s a widespread feeling that there’s nothing to be done.
The first thing to recognize is that this isn’t always how the present feels: often in the past, people had a sense that there was something—something huge — to be done. Essays like the Communist Manifesto give people this sense. Before that, at the dawn of modern democracy, documents like Common Sense (in the US) and the Declaration of the Rights of Man and of the Citizen (in France) gave people the same sense. There was something to be done.
Human nature, far from being fixed, is read differently from age to age. These different readings give rise to totally new ideas for institutions. And these new readings and new institutions seem to reshape us. Often, what works out in practice would have seemed impossible on the previous views. Furthermore, the traits we are supposedly balancing — autonomy, collective responsibility, equality, etc — are themselves changing. They, also, are expressions of one view of human nature or another.
Indeed, each of our present-day institutions can be traced to a vision of human nature which swept through society. Each new vision led designers to focus on different features of a desirable society, and to recognize different approaches as viable. This made new institutions attractive.