As no other purpose can be assigned, the text must be supposed to
represent Brahman as having joy for its head, and so on, for the purpose
of meditation. In order to accomplish the meditation on Brahman which is
enjoined in the text 'he who knows (i.e. meditates on) Brahman reaches
the Highest,' the text represents the Brahman consisting of bliss as
made up of joy, satisfaction, &c., and compares these to the head, the
wings, and so on. The Self of bliss, which is the inmost of all the
Selfs mentioned in the text, is by this means represented to the mind in
a definite shape; just as in the preceding sections the Self of food,
the Self of breath, and the rest had similarly been represented in
definite shapes, consisting of head, wings, and so on. As thus the
qualities of having joy for its head, &c. are merely secondary marks of
the Self of bliss, they are not necessarily included in each meditation
that involves the idea of that Self.