Don't go on discussing what a good person should be. Just be one.

One of the recurring themes in Marcus' handbook is leadership's responsibility to work intelligently with what it is given and not waste time fantasizing about a world of flawless people and perfect choices.

What we do in life ripples in eternity.

Always follow these two rules: first, act only on what your reasoning mind proposes for the good of humanity, and second, change your opinion if someone shows you it's wrong. This change of mind must proceed only from the conviction that it's both correct and for the common good, but not because it will give you pleasure and make you popular.

The stone that is thrown into the air is none the worse for falling down, and none the better for going up.

Treat with utmost respect your power of forming opinions, for this power alone guards you against making assumptions that are contrary to nature and judgments that overthrow the rule of reason.

The best revenge is to be unlike him who performed the injury.