To enter the Holy City—the Self, the center of one's being—one must rise above the height of the wall, 216. The mark of the beast, 666, when multiplied by itself (6 × 6 × 6), equals 216. The number 666 symbolizes one-half of a whole, given that 6 + 6 + 6 equals 18, which is half of 36 (360 degrees).

Occam’s Razor, a problem-solving principle attributed to the 14th-century philosopher William of Ockham, states that “entities should not be multiplied beyond necessity.” The height of the wall symbolizes the barrier we create by building upon information that confirms our biases rejecting any knowledge that challenges them.