Keter is the name of the first and highest sefira of the ten sefirot. However, Keter is not always counted as one of the ten sefirot. Just as a crown, a keter, on a person’s head encompasses him but is not part of his body, so too the sefira of Keter, due to its lofty status, can be considered above the ten sefirot. When Keter is regarded as part of the system, it is the highest part of the head, which is comprised of the first three levels: Keter, Ḥokhma, and Bina. When Keter is not included in the list of sefirot, it is substituted by Da’at, a structure that can be considered a pseudo-sefira.
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