‘The Behavioral Investor’ offers tips and tools to manage our emotions around money. : Many martial arts rely on what is referred to as the “Circular Theory of Self Defense,” meaning that the momentum and exertion of an attacker can actually be used to your advantage. Imagine being rushed by a would-be assailant who speeds toward you with arms extended. Rather than meeting the full force of his momentum head on, you might side step this rush, deflecting the outstretched arm, leading him to rush past, now vulnerable to counter attack.