There exists a law, not written down anywhere but inborn in our hearts; a law which comes to us not by training or custom or reading but by derivation and absorption and adoption from nature itself; a law which has come to us not from theory but from practice, not by instruction but by natural intuition. I refer to the law which lays it down that, if our lives are endangered by plots or violence or armed robbers or enemies, any and every method of protecting ourselves is morally right.
To reduce man to the duties of his own city, and to disengage him from duties to the members of other cities, is to break the universal society of the human race.
There is in fact a true law namely right reason, which is in accordance with nature, applies to all men and is unchangeable and eternal. ... It will not lay down one rule at Rome and another at Athens, nor will it be one rule today and another tomorrow. But there will be one law eternal and unchangeable binding all times and upon all peoples.
We can more easily avenge an injury than requite a kindness; on this account, because there is less difficulty in getting the better of the wicked than in making one's self equal with the good.
The happiest end of life is this: when the mind and the other senses being unimpaired, the same nature which put it together takes asunder her own work.