A noble man compares and estimates himself by an idea which is higher than himself; and a mean man, by one lower than himself. The one produces aspiration; the other ambition, which is the way in which a vulgar man aspires. ↗
The fundamental point in fabricating a chain reacting machine is of course to see to it that each fission produces a certain number of neutrons and some of these neutrons will again produce fission. ↗