When you look at the twigs and branches of bare trees, do you ever see pentagrams?
I thought so. Me too.
It's March in Minnesota: there are certainly plenty of bare branches to be seen, and the random patterns that they form as they move in the wind keep making pentagrams. Looking out the window this morning, I actually saw the pentagram before I saw the branches, as if it were standing in the foreground of my visual field, between me and the tree. Weird.
It's called pareidolia, literally “image instead of” (Greek eidôlon also gives us “idol”): the tendency of the human mind to interpret random stimuli meaningfully. Pareidolia is a type of apophenia, identifying patterns in random data. Our kind is really good at this; it's the basis, for example, of divination.
I used to wonder if it meant that I've been living in the broomstick ghetto too long. In Rosemary Edghill's novel The Book of Moons, one of our heroine's coven-sibs tells her, “Bast, you really need to get out more and read some history that doesn't have witches in it.”