Carl Jung: The debt we owe to the play of imagination is incalculable.

The dynamic principle of fantasy is play, a characteristic also of the child, and as such it appears inconsistent with the principle of serious work.

But without this playing with fantasy no creative work has ever yet come to birth. The debt we owe to the play of imagination is incalculable.
It is therefore short-sighted to treat fantasy, on account of its risky or unacceptable nature, as a thing of little worth.

It must not be forgotten that it is just in the imagination that a man’s highest value may lie.

I say "may" advisedly, because on the other hand fantasies are also valueless, since in the form of raw mate- rial they possess no realizable worth.

In order to unearth the treasures they contain they must be developed a stage further.

But this development is not achieved by a simple analysis of the fantasy material; a synthesis is also needed by means of a constructive method. Carl Jung, CW 6, Page 63, Para 93