It has been explained above (section 22) that Ze’er Anpin and Nukba56This refers the partzuf corresponding to Malkhut. on their own are unfit to receive brains,57The term “brains“ can be thought of as similar to the human concept of consciousness. When a person understands more, he or she can be thought of as “more conscious.” Similarly, when there are changes in particular levels, like when a level ascends to the level above it as a result of the process of maturity, it is described as having more “brains,” meaning increased exposure to the supernal light that is accessible at those higher levels. because the Malkhut of the attribute of judgment rules over them, and the force of the first constriction dominates Malkhut, preventing it from receiving the illumination of Ḥokhma.
We call this Malkhut of the attribute of judgment “manula” (lock) (as explained in Sulam on the introduction to the Zohar 59, s.v. “go”).