(Greek διάνοια) diánoia: from diá, "thoroughly, from side-to-side," which intensifies noiéō, "to use the mind," noús, "mind." Dianoia can be translated as understanding, discrimination.
"Jesus said unto him, Thou shalt love the Lord thy God with all thy heart, and with all thy ψυχή psychē, and with all thy διάνοια dianoia." - Matthew 22:37
"And we know that the Son of God is come, and hath given us διάνοια dianoia [understanding], that we may know him that is true, and we are in him that is true, [even] in his Son Jesus Christ. This is the true God, and eternal life." - 1 John 5:20
In esoteric psychology, the third of the Four States of Consciousness. In the Fourth Way schools, it is called Self-remembering, and is a state of actively directed conscious attention.
"Dianoia" was used by Plato to signify "understanding or intellectual activity" as a discursive process, in contrast with the immediate apprehension characteristic of noesis (related to Nous, the Fourth State of Consciousness).
"Dianoia is the intellectual revision of beliefs, analysis, conceptual synthesis, cultural-intellectual consciousness, scientific thought etc. Dianoetic thought studies phenomena and establishes laws. Dianoetic thought studies the inductive and deductive systems with the purpose of using them in a profound and clear way. " - Samael Aun Weor, The Perfect Matrimony