Anyone?

A monk asked Master Chao Chou, “Does a dog have Buddha nature?”
The Master answered, “Wu” (no). This single word “Wu,” besides being a mantra that is pronounced as a double “u” like imitating the sound of a hurricane, is also a Koan itself.
To work with the Koan “Wu” while having the mind still and in silence, is something marvellous.
The experience of the “illuminating Void” allows us to experience an element that radically transforms. -Samael Aun Weor, Cosmic Teachings of a Lama

Therefore, what is Holy Negation (the Second Logos, the Christ)? What does it mean to negate the illusions of the mind and thereby arrive at comprehension?

The mantra Wu is a Koan. Therefore, meditate on this koan while mantralizing the sacred sound, sifting through the contents of your mind through creative comprehension and stillness!