One of the interesting trends evident in Rapunzel tales is the element of irony: often a maiden is imprisoned in a tower for the purpose of shielding her innocence. Yet all these tales seem to end in her not only meeting a man, but becoming pregnant.
For example, in the Jewish tale "Solomon's Daughter," as found in Surlalune's Rapunzel and Other Maiden in the Tower Stories From Around the World, Solomon imprisons his daughter in a tower because he reads in the stars that she will marry a poor youth. However, an eagle carries a poor youth to the roof of the tower, where he and the maiden fall in love. It was the very act of keeping his daughter in a tower that enabled her to meet her poor lover.
This is very similar to Sleeping Beauty, in which the young princess pricks her finger on a spindle. The irony here is that her father the king had ordered all spindles banned to keep the thirteenth fairy's prophecy from coming true, yet because he did this, his daughter didn't even know what a spindle was. In both of these tales, if the father character hadn't attempted to thwart the prophecy, it may not have even come true; it may be one of those self-fulfilling prophecies that sets off the chain of events.
In many of the cultures in which these tales circulated, the people may have given more credence to prophecies in general, whereas today we tend to consider prophecies only as interesting features of fantasy and supernatural genres. We are fascinated by the concept of being able to see into the future and the potential implications, and the possibilities of multiple futures that depend on current choices.
Yet these tales may also have a very simple message: though parents may wish or try, they cannot keep their children from growing up. Sleeping Beauty's finger prick is often given sexual/maturational connotations; although her father is trying to prevent her death in the story, on a symbolic level he may be trying to prevent her from ceasing to be a child. The witch in Rapunzel can be seen as an overprotective mother, trying to keep her daughter in ignorance of the ways of the world; yet the world has a habit of making its ways known, and often trusting your children with (appropriate) knowledge is much better than attempting to keep them ignorant and naive. In the words of the witch at the end of "Into the Woods" when she sings, "Careful the things you say/Children will listen". As Time Magazine said about the original musical, its "basic insight ... is at heart, most fairy tales are about the loving yet embattled relationship between parents and children. Almost everything that goes wrong — which is to say, almost everything that can — arises from a failure of parental or filial duty, despite the best intentions."
Illustrations by A.H. Watson