Find the Dalmatian: There's a Dalmatian hidden somewhere in this picture. If you look for it, you're sure to find it, and once you do, you won't be able to imagine it without it.

Consider this: is that Dalmatian actually there, or did you just see it because you were looking for the dog in the picture? Is there a Dalmatian in this picture? If you look carefully, you can probably find it. The brain is very good at finding meaningful patterns.

The brain has an enormous capacity for pattern recognition. It sometimes goes so far in finding meaningful patterns in a chaotic whole that people start seeing things in all sorts of places that aren't actually there. One example is particularly striking: the so-called face on Mars. The world was turned upside down when scientists discovered a hill on Mars that resembled a human face. Had there been a civilization on Mars after all? The answer is no: it was the ability and need for pattern recognition that played tricks on us.