There is a positive force, meaning constructive, and a negative force, meaning negative and destructive. They create and complement the entire reality in general and particular through their harsh and perpetual war with one another. As we have said above, the negative force appears at the end of every political phase, elevating it to a better state, and thus the phases follow one another until they reach their ultimate perfection (...) In addition, being a social creature, the individual development is not enough. Rather, one's ultimate perfection depends on the development of all the members of society.