Also related : Schelling Fences and self-fulfilling correlations/prophecies.

I got confused by the title, thought it was about rationalist horoscopes, and almost didn't read it as a consequence (which would've been a shame, as it was pretty interesting and insightful). Maybe others didn't read it for similar reasons.

Here's a small riddle: What do the following three images have in common?

They're square matrices of 150 x 150 pixels.