Is It True? (IM 942)

The following ancient words from Eastern Philosophy sounds contradictory yet appealing.

"All warfare is based on deception. Hence, when we are able to attack, we must seem unable; when using our forces, we must appear inactive; when we are near, we must make the enemy believe we are far away; when far away, we must make him believe we are near.”

What meaning can be gain from above words? Is it true?