Sometimes the changes that are generated in a revolutionary period are rather trivial and do not last past the cycle. But sometimes, from a strong crisis, a revolution forges something new that lasts for centuries and represents progress toward values that are more rational and empathetic. In seeing this historical pattern, we must recognize what seems to be an overall human spirit that transcends any particular time and that keeps us evolving. If for any reason the cycle stopped, we would be doomed.