Astrology exists for the same reason any irrational myth exists: like all animals we have pattern-seeking brains, yet these brains are hardwired to cope only with very simplistic environments. Therefore we crave simplicity in the patterns we “find.” Hence seeing shapes in the starfield, believing in things like “luck” and “souls” as well as nonsense like astrology. Simple minds need simple ideas.

Instead of pausing to ask, “how would that work if it were real?” we immediately embrace the simplistic because our brains aren’t well adapted for thinking — it burns too many calories and during nearly all of our evolution as a species calories were scarce and uncertain. Not thinking, therefore, was a solid adaptation. And we’re still the same today.

Professional astrologers have capitalized on our credulity for millennia, crafting ambiguous or meaningless statements that can mean practically anything at all, knowing that confirmation bias will ensure the recipient fills in the gaps and thus believes that the “prediction” came true. Thus do the cynical profit from the credulity of the gullible, always and forever.