I consider myself an adult nowadays, much as I hate to admit it. Yet when I look around I see lots and lots of people who have the external trappings of adulthood (children, a house, a car, a riding lawnmower with headlights), and yet believe some of the most patently ridiculous things, mostly stuff they've just never really examined all too closely.

So, as the self-appointed cynical ass of the month, I feel it's time to take a brickbat to these illusions everyone seems to hold so dear deep inside (and sometimes not so deep inside) their souls:

• Bigfoot, the Yeti, and the Loch Ness Monster (and all the monsters like them) do not exist.

  I really believed in scary monsters like these for a long time, until I started learning more about endangered species. Depending on who you ask, pretty much any species of multi cellular life needs at least two to three hundred individuals to be viable in the wild. Anything less than this and they eventually inbreed straight to extinction.

  What does this have to do with scary monsters? Everything. It's quite exciting and credible to imagine a single monster giving us all the slip for hundreds of years, but two thousand monsters? We may never have seen giant squid (archeteuthis) alive, but the ammonia reek of their corpses is a regular feature of some beaches around the world. Yet nobody, not a single person, has ever found a Nessie corpse, or a dead Yeti, or the bones of a Bigfoot. All those interesting pictures, wild films, and footprints? Fakes. Every. Single. One.

• There's no such thing as ghosts

  I catch hell over this one regularly at home. Nobody, but nobody, has ever provided conclusive evidence such things exist. However, there's lots of evidence of people faking this stuff. So much so that nowadays I treat ghost "documentaries" like magic shows... I sit and try to figure out how they're faked. Most of the time, hell nearly all of the time, I can come up with an extremely rational reason for what is going on. Usually the reason is "money", or "attention", or "make rich, cute kids on MTV freak out". When I can't, it's more because the people faking it are more clever than I am (which, sadly, isn't all that hard) rather than an incontinent poltergeist rattling the windows.

  I tend to get a "money where your mouth is" challenge whenever I bring this up at home. Would I spend the night in a haunted house? Nope. I'm quite capable of scaring the beejezus out of myself without any help at all from creepy surroundings. But it's me scaring me, not some wobbly goblin. I also wouldn't put it past people who use "haunted" reputations to make money or attract attention to pay a few strong lads some extra money to sneak into that house at night to "help" the ghosts along with a bat or two across my head. I have an extreme suspicion this is the ultimate fate of nearly all the "ghost hunters" who "disappeared" trying to prove houses weren't haunted.

  This doesn't mean ghost stories aren't fun, or haunted houses aren't creepy. It just means they're fake.

• Horoscopes predict nothing but chance

  The zodiac calendars and books used by modern astrologers are all based on Aristotle's Almagest, a first-century A.D. almanac of the stars. The problem with the Almagest is the earth has a bit of a wobble. Two thousand years later, the sun has moved almost exactly one sign ahead of the calendars Astrologers use. That's right, you've never been the sign you think you are, you're the next one up. All the stuff people have been telling you about yourself that's predicted by your sign? The stuff that seemed to be describing you to a "T"? Wrong person. If it can be so convincing and yet so wrong, how can it be relied on at all?

  I distinctly remember a program on Nova years ago about psychic phenomena hosted by James Randi. They went to a high-school classroom and handed out horoscopes to everyone. Earlier, students had submitted some basic personal information, and Randi explained this information was used to create a specific horoscope for each member of the class. After a few minutes, Randi asked how many people's horoscopes matched them nearly perfectly. Slowly, almost every hand went up. He then asked them to pass their horoscope to the person behind them, so they could compare.

  Every horoscope was exactly the same.

  Astrology is fun, yes, and sometimes a horoscope can sound eerily familiar. But this is only because they're so general it's nearly impossible for them to be wrong. They're next to the comics in the newspaper for a reason.

People sometimes accuse me of trying to take all the magic out of the world when I say things like this. Personally, I think the world is an amazingly magical place. The vastness of the universe, the bizarre "foam" of quantum mechanics, the amazing subtlety of life itself, are all riotously colorful expressions of the wizardry that surrounds us all. What's even more amazing about them is they're real. The whole point of science is to prove stuff wrong, and all these things have been found to be true time and time again.

So please, don't waste any more money on astrology books, or bigfoot documentaries, or haunted houses. Go out and buy Stephen Hawking's latest book instead. When you open your mind to the way the universe really works, the wonder just happens.