The symbolic interpretation of causes by means of the energic standpoint is necessary for the differentiation of the psyche, since unless the facts are symbolically interpreted, the causes remain immutable substances which go on operating continuously, as in the case of Freud's old trauma theory. Cause alone does not make development possible. For the psyche the reductio ad causam is the very reverse of development; it binds the libido to the elementary facts. From the standpoint of rationalism this is all that can be desired, but from the standpoint of the psyche it is lifeless and comfortless boredom -- though it should never be forgotten that for many people it is absolutely necessary to keep their libido close to the basic facts. But, in so far as this requirement is fulfilled, the psyche cannot always remain on this level but must go on developing, the causes transforming themselves into means to an end, into symbolical expressions for the way that lies ahead. The exclusive importance of the cause, i.e., its energic value, thus disappears and emerges again in the symbol, whose power of attraction represents the equivalent quantum of libido.
The energic value of a cause is never abolished by positing
an arbitrary and rational goal: that is always a makeshift.
Psychic development cannot be accomplished by intention and
will alone; it needs the attraction of the symbol, whose
value quantum exceeds that of the cause. But the formation
of a symbol cannot take place until the mind has dwelt long
enough on the elementary facts, that is to say until the
inner or outer necessities of the life-process have brought
about a transformation of energy.... In civilized man the
rationalism of consciousness, otherwise so useful to him,
proves to be a most formidable obstacle to the frictionless
transformation of energy. Reason, always seeking to avoid
what to it is an unbearable antinomy, takes its stand
exclusively on one side or the other, and convulsively seeks
to hold fast to the values it has once chosen. It will
continue to do this so long as human reason passes for an
"immutable substance," thereby precluding any symbolical
view of itself. But reason is only relative, and eventually
checks itself in its own antinomies. It too is only a means
to an end, a symbolical expression for a transitional stage
in the path of development.