No one is so brave that he is not disturbed by something unexpected.
—Julius Caesar
The unconventional is generally the province of the young, who are not comfortable with conventions and take great pleasure in flouting them. The danger is that as we age, we need more comfort and predictability and lose our taste for the unorthodox. This is how Napoleon declined as a strategist: he came to rely more on the size of his army and on its superiority in weapons than on novel strategies and fluid maneuvers. He lost his taste for the spirit of strategy and succumbed to the growing weight of his accumulating years. You must fight the psychological aging process even more than the physical one, for a mind full of stratagems, tricks, and fluid maneuvers will keep you young. Keep the wheels turning and churning the soil so that nothing settles and clumps into the conventional.
Daily Law: Make a point of breaking the habits you have developed, of acting in a way that is contrary to how you have operated in the past; practice a kind of unconventional warfare on your own mind.
The 33 Strategies of War
, Strategy 24: Take the Line of Least Expectation—The Ordinary-Extraordinary Strategy