Apart from selfish reasons, such as fear of punishments, fear of blame, of dishonour, etc, there remains only two motives that can stop (or prevent, "empâecher", Fr.) men from acting badly; the natural sense of commiseration (or "sympathy", - "commisération", Fr.) for one's fellow men - compassion, and the influence of education, by association of ideas ("par l'association d'idées", Fr.) - habit.
See that unfortunate soldier who is falling hurt to death ("tombe blessé à...", Fr.) on the battlefield; he learns that his folks have vanquished and dies happy. He detached himself from himself (s'est détacher de lui-même", Fr.), has identified himself with something greater and more lasting than himself; his homeland ("patrie", Fr.); thus, while dying as an individual, he has the certainty to survive in a larger existence.
A man, engaged in his simple reflections in everyday life, will comprehend neither the possibility, nor the benefits of self-sacrifice, but, when given ("qu'on lui donne", Fr.) a great cause to defend, and he will find only natural to sacrifice oneself for it.
If pity was always equally alive and acting in all individuals and in all circumstances, we could do away with moral. Unfortunately, it is not compassion, but rather it's contrary, selfishness, that act most strongly in us.
Up to here, in general, we have mainly stuffed the brain of the young people with a indigestible multitude of varios notions, without thinking about enough of the prime necessity to form their character.
The appalling and shameful scene ("spectacle", Fr.) of disarray and illogicality that manifest itself in the thought and deeds of men, will no longer be seen, once these will possess an enlighten consciouness.