Pareidolia sounds like an unfortunate infectious disease of some kind but the truth is a lot more interesting. Pareidolia is the name given to the human propensity for seeing meaningful shapes in random patterns. This ability of ours can be delightful when we recognise that the shapes and connections we see are the result of our own imagination, such as seeing faces, animals and objects in the clouds. Unfortunately there is a tendency also for us to see purpose in the things that surround us so that some people, when they see a face in the knot of a tree, might ascribe to it meaning beyond what is there.
For example it is common for people to convince themselves they see the figure or face of religious icons in natural formations and read messages into these images. Whether or not these visions are accurate are beside the point but I’m not aware of any extant pictures of these personalities from their own time period so how do people know what they look like?
It would seem that we are capable of seeing things in randomness that make sense to us, perhaps this pattern recognition helped our ancestors see predators or prey in long grass or wooded areas. I can see how being able to piece together a lion from incomplete glimpses of it would be handy. This pattern recognition does not seem to be limited to sight though, we can also read meaning into noise and static, this has become the basis of the phenomena known as EVP. EVP stands for Electronic Voice Phenomena and is touted by some as conclusive evidence of the existence of ghosts, but I’ll cover that some other time.
http://thefolklorist.com/Pareidolia%20Project/index.htm -Java required.