The Wisdom of Kabbalah and Philosophy
Philosophy loves to pride itself on understanding all the negatives [does not state who He is, but rather who is not Him] about His essence. However, the sages of Kabbalah put their hand to their mouth at this point [when the Creator Himself rather than His manifestation with relation to us is being discussed], and do not give Him even a simple name, for we do not define by name or word that which we do not attain. That is because a word designates some degree of attainment [based on the perception of the attained object in our senses].
However, Kabbalists do speak a great deal [to the extent of the researcher being similar to the properties of the Light] about His illumination [His manifestation with relation to us] in reality, meaning all those illuminations they [researchers themselves] have actually [practically, in sensations] attained [within themselves], as validly as [our] tangible [world, meaning the reality which we sense from the beginning through our inherent qualities] attainment [of objects and properties].
– Baal HaSulam “The Wisdom of Kabbalah and Philosophy”