The human brain is really quite good at seeing patterns. That’s mostly a positive thing: it helps us recognize faces, spot danger and discover important new things. Unfortunately, that same tendency to see patterns in everything can lead to seeing things that don’t exist.

Seeing recognizable objects in random or unrelated objects or patterns is called pareidolia. It’s a form of apophenia, which is a more general terms for seeing apparently meaningful connections between unrelated patterns. Everyone experiences it from time to time. For example, nearly everyone occasionally sees animal or human shapes in clouds. 

Much like with optical illusions, our brains struggle to comprehend the notion that some things just don't make sense and that chaos and randomness are all around us. 

Such patternicities, then, mean that people believe weird things because of our evolved need to believe nonweird things!