There is some doubt as to whether he actually wrote that book.
The term homunculus means "little man," and can be used in many symbolic ways. For instance, we are homunculi, because we have the shape of human beings, but are not human beings yet.
So in general, particularly considering our current condition, this is something without immediate practical value.
“Nothing is easier than self-deceit. For what each man wishes, that he also believes.” —Demosthenes
"Do not worry; cultivate the habit of being happy." —Samael Aun Weor