Sentence:  At the same time the multiple transvestitism involved - the fat man as girl and as baby , as coquette pretending to be a baby - touches for a moment horrifyingly upon the secret sources of a life like Jacoby 's , upon the sinister dreams which form the <WSD>sources</WSD> of any human life . 
Meaning of the word marked with <WSD> tags:  anything that provides inspiration for later work