There are two aspects of the principle of Jū that are in constant operation, both interchangeable and inseparable. One aspect is that of "yielding", and is manifest in the exponent's actions that accept the enemy's force of attack, rather than oppose him by meeting his force directly with an equal or greater force, when it is advantageous to do so. It is economical in terms of energy to accept the foe's force by intercepting and warding it off without directly opposing it; but the tactic by which the force of the foe is dissipated may be as forcefully made as was the foe's original action.