6. The manner in which these notions come into being is as follows. Men being all naturally inclined to sexual intercourse, and the consequence this being the birth of children, whenever one of those who have been reared does not on growing up show gratitude to those who reared him or defend them, but on the contrary takes to speaking ill of them or ill-treating them, it is evident that he will displease and offend those who have been familiar with his parents and have witnessed the care and pains they spent on attending to and feeding their children. For seeing that men are distinguished from the other animals possessing the faculty of reason, it is obviously improbable that such a difference of conduct should escape them, as it escapes the other animals: they will notice the thing and be displeased at what is going on, looking to the future and reflecting that they may all meet with the same treatment. Again when a man who has been helped or succored when in danger by another does not show gratitude to his preserver, but even goes to the length of attempting to do him injury, it is clear that those who become aware of it will naturally be displeased and offended by such conduct, sharing the resentment of their injured neighbor and imagining themselves in the same situation. From all this there arises in everyone a notion of the meaning and theory of duty, which is the beginning and end of justice. Similarly, again, when any man is foremost in defending his fellows from danger, and braves and awaits the onslaught of the most powerful beasts, it is natural that he should receive marks of favor and honor from the people, while the man who acts in the opposite manner will meet with reprobation and dislike. From this again some idea of what is base and what is noble and of what constitutes the difference is likely to arise among the people; and noble conduct will be admired and imitated because advantageous, while base conduct will be avoided. Now when the leading and most powerful man among people always throws the weight of his authority the side of the notions on such matters which generally prevail, and when in the opinion of his subjects he apportions rewards and penalties according to desert, they yield obedience to him no longer because they fear his force, but rather because their judgment approves him; and they join in maintaining his rule even if he is quite enfeebled by age, defending him with one consent and battling against those who conspire to overthrow his rule. Thus by insensible degrees the monarch becomes a king, ferocity and force having yielded the supremacy to reason.