explanation has been provided in the earliest body of literature that
has come down from antiquity. I refer to the Egyptian "Pyramid Texts".

Before this ancient testimony is examined certain general principles
involved in the discussion of such problems should be considered. In
this connexion it is appropriate to quote the apt remarks made, in
reference to the practice of totemism, by Professor Sollas.[7] "If it is
difficult to conceive how such ideas ... originated at all, it is still
more difficult to understand how they should have arisen repeatedly and
have developed in much the same way among races evolving independently
in different environments. It is at least simpler to suppose that all
[of them] have a common source ... and may have been carried ... to
remote parts of the world."

I do not think that anyone who conscientiously and without bias examines
the evidence relating to incense-burning, the arbitrary details of the
ritual and the peculiar circumstances under which it is practised in
different countries, can refuse to admit that so artificial a custom
must have been dispersed throughout the world from some one centre where
it was devised.

The remarkable fact that emerges from an examination of these so-called
"obvious explanations" of ethnological phenomena is the failure on the
part of those who are responsible for them to show any adequate
appreciation of the nature of the problems to be solved. They know that
incense has been in use for a vast period of time, and that the practice
of burning it is very widespread. They have been so familiarized with
the custom and certain more or less vague excuses for its perpetuation
that they show no realization of how strangely irrational and devoid of
obvious meaning the procedure is. The reasons usually given in
explanation of its use are for the most part merely paraphrases of the
traditional meanings that in the course of history have come to be
attached to the ritual act or the words used to designate it. Neither
the ethnologist nor the priestly apologist will, as a rule, admit that
he does not know why such ritual acts as pouring out water or burning
incense are performed, and that they are wholly inexplicable and
meaningless to him. Nor will they confess that the real inspiration to
perform such rites is the fact of their predecessors having handed them
down as sacred acts of devotion, the meaning of which has been entirely
forgotten during the process