We can perhaps try to mitigate their worst effects, but to try to imagine old age with the body of a young person is an exercise in fantasy. On the other hand, some persons think of the infirmities of old age as a sickness, and as we learn more about how the body works, we may learn how to eliminate them. In this view, it is not crazy to imagine healthy old age, it is just a matter of learning what causes the body to self-destruct, and to fix it. Now, we have the same split in our understanding of conflict. Some thinkers believe that conflict is as much a part of the human condition as being bipedal, or old age.
Humans are selfish and distrustful animals.
In this view, the main reason we need government is for mutual protection, and that is its main function. The Leviathan is one of the most influential political books of all time. The first makes man invade for gain. The second, for safety. The third, for reputation.