The artist must bow to the monster of his own imagination.

The line suggests that creative work is ultimately governed by the artist’s own inner compulsions—visions, fears, obsessions, and invented “monsters” that demand expression. To “bow” implies submission: the artist may wish to control the imagination, but the imagination can become the dominant force, setting the terms of what must be made. Read this way, the quote frames art as a kind of necessity rather than a freely chosen pastime, and it hints at the psychological cost of creation: the same imaginative power that enables art can also tyrannize the artist, forcing confrontation with troubling material that cannot be ignored.