James L. Cambias's Blog, page 45

PhilCon 2016, Featuring ME!

This weekend I'll be attending the venerable PhilCon science fiction convention, at the Crowne Plaza hotel in scenic Cherry Hill, New Jersey. Here's my schedule of events:

Friday, November 18, 8:00 p.m., Plaza III: Utopias That Make Us Cringe ��� I'll be moderating a panel on utopian societies in science fiction that don't actually seem very utopian at all.

Saturday, November 19, 10:00 a.m., Executive Suite C: Taking Your Game from Concept to Creation ��� I join a distinguished group of panelists to discuss how to actually design and publish a game.

Saturday, 11:00 a.m., Crystal Ballroom Three: Writing For Aliens: Constructing Languages ��� This time I'll be the most obscure member of a powerhouse panel talking about alien communication.

Saturday, 3:00 p.m., Plaza II: Psionics: Where Did They Go? ��� A group of writers tackle the question of why psychic powers were once ubiquitous in science fiction and why that has changed.

Sunday, November 20, 12:00 noon, Plaza II: The Prehistory of SF ��� I'll be moderating a panel about early works going back to ancient Rome, in which we try to settle whether or not they were science fiction and how they influenced the field.

Movie Magic

Last weekend the family went out to see Dr. Strange, the latest Marvel Comics movie. This one is the origin story for Dr. Stephen Strange, Sorcerer Supreme and master of the mystic arts. It was entertaining and visually wonderful. It did get me thinking (uh-oh) about how magic is depicted in most modern films ��� and in a lot of modern fantasy fiction and games. "Cinematic magic" has several recognizable features:

Spells are cast quickly
Showy visual effects
Physical effects are immediate and un-ambiguous
Effectiveness depends on the skill and personal "power" of the magician
No spiritual cost

This is the magic of Dr. Strange, of Harry Potter, the film incarnations of Gandalf and the White Witch, the witches of Bewitched, and on back past the Wicked Witch of the West all the way to The Magician by Georges Melies. In games this is how characters do magic in Dungeons & Dragons, Fantasy Hero, the World of Darkness, and most other roleplaying systems. And, unsurprisingly, it is how magic works in the hybrid child of tabletop games and cinema, electronic games. You do the spell and stuff happens.

What's interesting about this is how different it is from how magic is described throughout the ages by people who believe it's real. "Real" magic rituals take forever to perform, often involving days of fasting and purification beforehand. They tend to involve a lot of physical apparatus ��� inscribed charms, ointments, potions, figures, ritual circles and other paraphenalia. In fairness to "real" magicians, they don't have access to post-production visual effects the way moviemakers do, so naturally they need to rely more on stage-dressing and psychological preparation.

While the spell-casting process is a lot more cumbersome and visible than cinematic magic, the effects of "real" magic are often much more subtle. Do this and you will have good fortune, or success in love, or prophetic dreams. Your enemies will get sick or have nightmares. There are exceptions: I've read Greek magical formulas for making corpses talk or to turn yourself invisible. But it's remarkable how few "fireball" spells there are in real books of magic. (This is one distinct difference between the Lord of the Rings films and Tolkein's novel ��� in the book Gandalf's magic is much more subtle and ambiguous.)

Similarly, while skill and preparation are important in "real" magical operations, there's a lot more randomness and wiggle room. Wizards can always fail, even if they did everything right. (This is a very handy excuse to tell the mark when you're using "real" magic to accomplish the only thing it's really good for: conjuring money from the pockets of gullible people into the hands of magicians.)

One very important element of "real" magic is entirely absent from cinematic sorcery: spirits. Most "real" magic involves summoning spirits, communicating with them, learning from them, and making them do the wizard's bidding. That's how "real" magic generally works: you get a spirit to do something. And by spirits, we mean elemental beings, the souls of dead people, "planetary intelligences," angels . . .

. . . but mostly we mean demons. Which brings me to the final big difference between cinematic sorcery and the stuff real people worried about until they could blame corporations instead: movie magic isn't going to cost your soul. It's morally neutral. Bad people like Voldemort or the Wicked Witch of the West may use spells to cause harm, but it's the causing harm that marks them as evil, not the using spells. Whereas for most of human history, in most cultures, just doing magic is enough to damn you eternally. Even if you might get away with a little harmless "folk magic," the moment you start calling up spirits, you've doomed yourself.

This last points up the common thread of what separates cinematic magic from real magic: it's technological. After all, technological devices tend to work quickly; flip the switch and the light comes on. They have unambiguous effects; pull the trigger and the gun blows a hole in something. They work reliably; click on the Word icon and the application loads (unless you messed up when installing it). And technology (as everyone but a few "Deep Greens" will admit) is morally neutral; the same rocket can launch a weather satellite to save millions of lives from typhoons, or put a warhead on target in an undefended city.

Unsurprisingly, the "technological" style of magic began to appear as the world became more technological. In The Tempest, Shakespeare's Prospero accomplishes all his wonders through the agency of his tame spirit Ariel. In A Midsummer Night's Dream, even the King of the Fairies has to make use of a love potion made from a flower to trick his Queen.

But by the time L. Frank Baum began writing the Oz books, magic had become as mechanistic as a clock or a locomotive. In fact, his amazing final novel, Glinda of Oz, is full of what can only be called magical steampunk technology, with submarines, a domed city that rises and sinks ��� all of it operated by complex machinery which is powered by magic.

And I think this explains why cinematic magic has completely eclipsed "real" magic, at least in entertainment. The genuine wonders of science and technology left real magic in the dust. Want to fly? You don't have to sign a compact with the Devil and coat yourself in some kind of nasty goop made of nightshade and baby fat; just hop in a plane. Pass the written exam and put in some practice time with an instructor and you can fly it yourself. Looking for buried treasure? You don't have to mess around with stealing corpses and making them tell you where they hid gold, just buy a metal detector (50 bucks at Wal-Mart). Everyone can do magic now.

With technology providing wonders beyond the imaginations of preindustrial wizards, on demand and reasonably-priced, fictional sorcery had to leapfrog ahead, doing things machines can't do (yet), but with the same reliability and moral neutrality people have come to expect. It's notable that "real" magic in the modern world tends to focus on precisely those areas most resistant to technological obsolescence: personal relationships, psychological support, and questions about the soul and the afterlife.

All of which goes to explain why, even though I've written fantasy stories and plan to write more, I call myself a science fiction writer. I know what true magic is: spells that can show me other planets, creatures living inside rocks, and devices to put the power of the Sun at our fingertips. Beat that, Dr. Strange!

Game Mechanics (Part 2): Why They Don't Matter

In my last post on the subject, I wrote about how important it is for game mechanics to replicate the reality of whatever the game is about. And then I left on a cliffhanger by saying that isn't actually true.

It's not true because games depend on the players.

A game is not a novel or a film. Those are finite created works which can be evaluated on their own terms (or on any terms the critic wishes to apply). You don't need to poll other readers to judge a novel or a film. The creator probably wants a lot of people to like his work, especially if he's doing it for money, but each reader or viewer ultimately interacts with the work alone. Even when we're in a crowded movie theater, we are responding to that film as individuals.

A game is more like a stage play or an improvisational comedy show. In fact it's possibly significant that we use the word "play" to refer to both a theater performance and the act of experiencing a game. All of those things depend on the players involved, and there is no "final edit" to change things.

If you're writing a novel you can edit your manuscript over and over again. If you're making a movie, you can edit the film, re-shoot scenes, and tinker endlessly. But a live performance doesn't have that luxury, which makes each one a unique event. Avid playgoer know that on some nights the performance is simply better than on others, even with the same cast, the same theater, and the same director. Sometimes everyone is just "on" and everything "clicks" ��� and sometimes everything doesn't.

The same is true with a game: the fun of a game session comes from the players, not the game. In the past I've ranted about Monopoly, the game literally designed to be no fun, with almost no connection between subject and mechanics. (Seriously: if you own a hotel on Mediterranean Avenue, why do you have to pay rent on Park Place? Why not stay in your own hotel for free? It doesn't make sense!) And yet Monopoly is one of the best-selling games in history. Obviously millions of people have enjoyed the hell out of playing Monopoly, because it's fun to sit around the table with friends or siblings and demand fistfuls of orange play money from them.

And with roleplaying games the fun is even more linked to the players and the gamemaster. A good GM can use just about any rules to create a fun session. A bad GM, or a lack of chemistry in the group, can scuttle even the most well-crafted scenario with the most elegant rule set. Heck, even a skilled group who get along well together can have an "off night" where things just don't work well.

So the secret to an entertaining game is this: find good players, and be a good player. Ultimately you only get what you bring to the table.

Biology of the Body Snatchers

(Note to everyone who is still sitting on the edge of their seat waiting for the promised follow-up to my last post: be patient. It's Halloween today so I'm doing a Halloween post.)

This past weekend I took my son to see the original Invasion of the Body Snatchers (1956) at Amherst Cinema. It was extremely entertaining for both of us. Some old "classic" films don't actually age well, but Body Snatchers held up very well indeed. I suspect it's because the movie has some really good actors in it, and the only fantastic elements shown on screen are some big paper-mache seed pods and a couple of wax dummies which are supposed to look like wax dummies. There's no monster suit to see the zipper on.

However, it did make me start wondering about the actual biology of the alien "Body Snatcher" organisms. From the film we know that they arrived on Earth in the form of seeds, drifting through space (more on this anon). The seeds grew into the big pods which (somehow) duplicate the forms and steal the minds of nearby living things. (Exactly what happens to the originals afterward is never mentioned; we don't ever see the Pod People disposing of bodies.)

While nobody in the film actually gets around to dissecting one of the duplicates, the movie strongly suggests that their impersonation of humans is complete, right down to the internal organs. The only difference between the Pod People and real humans is their lack of genuine emotion. (Though one wonders what a DNA test would reveal.)

But I find myself wondering: what are the Pod People for? What evolutionary purpose do they serve? What part in the Body Snatcher life cycle do they play?

On Earth we see the duplicates actively cultivating the pods and distributing them, but that requires a species capable of agriculture for them to mimic. What happens if the pods grow on a planet ��� or even in a remote location ��� with no intelligent life? What can the Body Snatchers accomplish by duplicating, say, mountain lions, or pronghorn antelopes?

Much depends on how innately intelligent the Body Snatchers are. If they are an intelligent species, then duplicates of animal species could still act as "farmers" to cultivate and spread the pods. The trouble is, I don't believe that. How can you have intelligence when your brain is a perfect duplicate of the brain of a species which isn't very intelligent? Unless you assume that the intelligence of the Body Snatchers comes from having an immaterial soul ��� but the single distinguishing feature of the duplicates is their utter soullessness.

One might posit that the Body Snatchers only take over intelligent life; their seeds remain dormant or are harmless weeds until a proper host evolves on the target world. The difficulty there is how such a system could evolve. The sheer time scale of interplanetary seed dispersal means you simply don't get many generations of Body Snatchers to evolve into perfect duplicators of alien life. If you limit their impersonations to intelligent life, the number of suitable target worlds is so tiny that it's a wonder any Bodies ever get Snatched.

So the Body Snatchers must have a simpler role: mere instinctive protection of the growing pods and maybe a little seed dispersal. That's still an enormous advantage. A plant which has animals selflessly defending it from predators and pests gains an immense boost in reproductive success. Consider how much of the Earth's surface is covered by corn, which worked out that trick in collaboration with the ancient human inhabitants of Mexico.

In that scenario, the intelligence of the human-duplicate Pod People in the film may be the first time the species has ever been truly intelligent. The invasion of Earth isn't just bad news for humanity, it's a menace to the entire Galaxy! A plant species which can enslave an entire technological civilization to disperse its seeds across space can literally conquer all lifebearing worlds. Only a technologically superior civilization might ��� might ��� be able to fend them off. Maybe that's what the terrifying robot Gort in The Day the Earth Stood Still is really for: not preventing interplanetary war, but making sure Earth hasn't been colonized by Body Snatcher pods. He's a flying-saucer piloting Department of Agriculture.

Other Times, Other Places

Maybe I'm overstating the Body Snatcher menace. In order to get their seeds onto other worlds, the Snatcher plants must send out an absolutely enormous number of spaceborne seeds. This, in turn, suggests that it's not uncommon for a planet to be hit by more than one seed in its history. Is it really likely that the Santa Mira infestation of 1956 is the first time a Body Snatcher sprouted on Earth? 

Perhaps the native life forms can fight back. After all, when the Body Snatchers enslave native organisms to defend the growing pods, that's obviously going to be bad for those organisms. They won't reproduce, and may not live as long (the Pod People don't love, and seem to be rather careless drivers). Maybe an infestation gradually burns itself out, occupying a region but gradually getting out-competed by un-duplicated native organisms. And of course there would be strong evolutionary pressure to develop resistance to duplication.

And even during historical times it's possible that humans beat back other infestations, without even really understanding what they were accomplishing. Consider the various "witch panics" in Europe, Africa, and elsewhere during the Early Modern period. Were those "witches" who aroused such unreasoning hatred really Pod People? Ironically, a modern, mobile, high-technology, tolerant society might be more vulnerable to the interstellar plant menace than an isolated medieval culture. 

Still: make sure to check under the bed before you sleep tonight. Might be a pod under there.

 

 

 

 

Game Mechanics (Part 1): Why They Matter

When I'm not writing science fiction I write roleplaying games, and I've also designed a couple of card games. As a result, I think about game rules more than most people.

Most games have simple, highly artificial mechanics. You have to assemble a certain set of cards, or eliminate your opponent's pieces by moving your own in highly constrained ways, or move around a board exchanging play money for properties.

The games I like to write ��� and play ��� have more complex mechanics which try to emulate some version of reality. What do I mean by "some version of reality?" Well, tabletop wargames, and their mutant offspring tabletop roleplaying games, originally tried to be as "realistic" as possible. Some of the wargames tried to model every aspect of commanding a military operation, down to the minutiae of logistics and morale.

In roleplaying game circles there were tremendous arguments about the lethality of gunshot wounds or sword-cuts, and whether longbows or crossbows should do more damage. Possibly the ultimate example of obsessive realism in roleplaying games is the landmark GURPS system from Steve Jackson Games, which promised complete accuracy, in-depth research, and accurate simulation. It could then serve as the common platform for games in a variety of settings, from an alternate-history Steampunk Europe to future Mars.

However, even as realistic game mechanics were reaching their apogee in the early to mid 1980s, there was a revolution in roleplaying going on. Games like Call of Cthulhu and the Star Wars Roleplaying Game from West End Games abandoned the idea of accurately modeling the "real world" in favor of simulating the reality of a fictional setting. In the real world people don't go mad when they see something bizarre and unnatural, but in Call of Cthulhu characters could lose "Sanity Points" from encounters with unearthly monsters ��� because that's what happens to people in Lovecraft stories. In the real world being an ace airplane pilot doesn't make you a good race-car driver, but in Star Wars both were controlled by your "Mechanical" ability ��� because in the Star Wars universe, being able to fly a cropduster means Luke is an expert space fighter pilot.

In short, designers began to realize that the game mechanics should enable players to do the things which are the reason they are playing the game in the first place. If you're playing a "swashbuckling" game of swordplay and derring-do, then witty banter and acrobatic stunts should be a key part of sword fights ��� which means that the rules should not penalize characters for trying to do other things while fighting.

A corollary of that principle is that characters will wind up doing the things that the game has rules for. If your game has a 50-page section on combat and one paragraph about social interaction, the players will try to solve most problems with violence.

When Kenneth Hite wrote his masterful GURPS: Cabal supplement he included an enormous amount of new rules on how to cast magic spells; as he put it in his designer's notes, he wanted to make magic rituals as detailed and complex as shooting a gun in GURPS. The expanded magic rules meant players would put in the effort, getting their characters into mystically-significant places on auspicious dates to cast their spells, instead of just rolling dice to fire them off. When the rules are detailed, players know this is important stuff and pay attention.

The creators of the James Bond 007 roleplaying game from Avalon Hill understood that principle very well: the game devotes as much space to gambling, car chases, and seduction as it does to fighting. The rules tell the players what they should expect to do.

My roleplaying work has all been setting and sourcebook creation, with rules devised by others. But my card games for Zygote Games were my own invention. Since Zygote Games's mission is to prove that educational games need not be lame, I made it a point to couple the game mechanics tightly to the reality of the subject of the game. In Bone Wars the players are taking the roles of paleontologists, so they do the things paleontologists do: collect fossils, make reconstructions, and argue with each other in the scientific journals. In Parasites Unleashed the players control parasites, going through complicated life cycles to grow, mate, and reproduce. In both cases the rules reflect the reality of the subject, so that by learning the game the players learn something about real science.

So when creating a game, remember that the rules define reality, not the other way around. They tell the players what they can do, and thereby inform them what they should do. Your game mechanics should be linked tightly to "reality" (real or fictional) of the things the characters or players will be doing.

And next time I'm going to explain why all this may be irrelevant.

The Worst Science Fiction Writer Ever

The time has come to talk about the worst science fiction writer in the history of the field. I'm not talking about any obscure pulp-era hacks, or nameless amateurs chronicling the exploits of Ensign Mary Sue. I'm talking about a writer whose ineptitude has been splashed across movie screens for everyone to see.

George McFly, the hapless father of Marty McFly in Back to the Future.

Consider the evidence: in 1955 he's an aspiring but unpublished science fiction writer, who lacks the confidence to submit any of his stories until he gets a midnight visit from a mysterious space-suited figure claiming to be "Darth Vader from the planet Vulcan." Convinced that his ideas about space exploration and aliens are real, George becomes a successful author.

What kind of a writer has to believe his fiction is true? I don't believe there are real Ilmatarans out there; I'm reasonably sure there are intelligent beings elsewhere in the Galaxy, but even if I didn't I could still write stories about them. I don't believe it's possible to travel faster than light but I can still use the magic wand of FTL to get reasonably contemporary humans into contact with aliens in distant star systems in my fiction. It's called imagination.

But that's not the worst of it. On top of his oddly literal imagination George McFly also shows a massive lack of intellectual curiosity. Eleven years after his mysterious midnight encounter with the man from "Vulcan" he could have turned on his TV and seen a science fiction show prominently featuring a character from the planet Vulcan ��� Star Trek. It's absolutely inconceivable that a science fiction fan in 1966 could have not been aware of that. Yet George McFly never seems to have wondered about the remarkable coincidence. He didn't contact Gene Roddenberry to ask if he had his own encounter with "Darth Vader" in the 1950s.

Now, maybe George saw Spock on Star Trek and chuckled over the use of the planet Vulcan as his home. After all, Vulcan as a fictional world pre-dates both George and Star Trek; Urbain LeVerrier proposed it as the name for a hypothetical infra-Mercurian planet in 1859.

But eleven years after that, the most popular science fiction film in history came out, featuring a character named Darth Vader. There's no way George McFly could have dismissed that as coincidence. The name was original. Did he think about it at all? Speculate about the possibility that he had visions of the future, or perhaps was visited by a time traveller? Did he ask local scientific expert Dr. Brown about it? Apparently not.

Even when his teenage son Marty grew into an exact duplicate of a teenager who befriended him back in 1955, and began hanging around with an eccentric local inventor, George didn't make the connection. (And for those of you making snide insinuations about the other possible explanation for a man's son looking like a boy his wife was infatuated with in her teens, recall that young Marty was born a good thirteen or fourteen years after his 1955 avatar vanished. Get your minds out of the gutter.)

Even if you assume George could somehow explain away the mystery, he's still a bad writer because he doesn't notice some great material staring him in the face! Regardless of whether or not he believes something strange happened to him in 1955, he could certainly weave those bizarre coincidences and unexplained events into a story ��� maybe even a screenplay. The fact that George McFly didn't write Back to the Future is proof that he's the worst science fiction writer ever.

Kitchen Report: Home-Made Boudin

Boudin ("boo-dan") is a French word for sausage, probably cognate with the English word "pudding" ��� which becomes less weird when you remember that the original English puddings were a mess of suet and flour wrapped in cloth and boiled. In Louisiana, the term became specific to Cajun sausages using rice as a filler. Boudin rouge is made of pig's blood, because when you're a poor Cajun farmer you're not going to waste all that protein and iron rich stuff. Boudin blanc leaves out the blood (and just to maximize confusion, there's a French sausage called boudin blanc which is a blend of pork and veal). I've been meaning to make boudin at home, and this past week I finally decided to tackle the project.

I chose boudin blanc because I don't know where I could get pig's blood around here and didn't feel like waiting for prom night at the local high school. It does call for pork liver, which doesn't show up often at my local supermarkets but is available at a specialty meats store down in Chicopee. So, equipped with a pound of pork liver and two pounds of "boneless country-style ribs" (i.e. pork loin strips) I got started. 

Since I didn't want to work with hot ingredients, I braised the pork a day in advance with bay leaf and salt until the meat was falling apart. This also gave me a pot full of pork stock, which I kept handy.

Then on the Big Day I sauteed my pork liver in the bacon drippings from that morning's breakfast (because there is no dish which can't be improved with some bacon fat) and cooked a cup of rice. I combined the liver, cooked pork, an onion, and some garlic in the Cuisinart and chopped it all into coarse shreds. Then I mixed all that with the stock (it was actually more of a jelly after being in the fridge overnight), spices, a bunch of chopped green onion, and the rice. Now I had a big bowl of boudin stuffing, ready to turn into sausage!

I have a hand-cranked meat grinder/sausage maker, and so I began to set it up, thinking proudly that the hard part was done. That's when I discovered the big flaw in my whole plan.

Boudin is not one of your finely-ground sausages. The filling has recognizable grains of rice and bits of onion in it. So I didn't want to push my filling through my meat grinder again because that would turn it all into paste. But when I tried to set up the grinder without the blade and screen assembly I realized that those components anchor the auger device, which pushes the filling through the blade into the sausage casing. Without the blade and screen, the auger just rattles around ineffectually within the barrel of the grinder.

So I had to stuff my sausage by hand. I bunched up the casing on the bottom of a funnel and started stuffing. Instead of a hand-cranked auger using mechanical advantage to speed the job along, it was just my finger, packing stuffing into the casings one cubic inch at a time. Over and over again, for the better part of an hour.

I got two casings filled, stuck the bowl of stuffing in the fridge, and steamed what I had made for dinner. Verdict: delicious. Next time I think I will increase the proportion of rice to meat. The recipe I used had a roughly 4:1 ratio, and as a result the rice sort of disappeared into the mass of pork.

After dinner I had a little sit-down, then cracked my knuckles and went back to stuffing boudin. It took me another hour to use up the rest of the filling, and by the end my finger was very stiff and wrinkly. But I had a couple of pounds of genuine home-made boudin to store in the freezer, so overall it was a success.

Lessons learned:

��� I can make pretty good boudin!

��� Next time I do this I'm going to find a mechanical stuffer.

��� When you are stuffing pork liver into sausage casings by hand, your dog will sit at your feet and watch for an hour, just for the chance to lick your hand when the job is done (she also got the empty bowl).

Science to the Rescue!

In the past I have mentioned my love of doing research and my focus on getting things right in my writing. Along the way I've pointed out how frustrated I get when moviemakers don't bother trying for accuracy.

Well, it turns out I'm not alone. The mighty National Academy of Sciences apparently also makes angry snorting sounds when it goes to the movies, and likes to go on at length about stuff the movie got wrong during the drive home afterward. But since the NAS is a prestigious organization with a public-education mission, it could actually do more than write some huffy blog posts.

Now there's a science accuracy hotline for moviemakers ��� and, presumably, for television and computer-game creators, as well. It's called the Science and Entertainment Exchange. The magic number is 1-844-NEED-SCI, or you can go to their Web site. The Exchange puts science-starved screenwriters in touch with Real Scientists who can help them.

What's especially nice is that the scientists at the Exchange seem to understand the difference between Getting It Right on science and technology details and winking at the "allowable magic" required to tell fantastic stories. A scriptwriter calling for help about an Incredible Hulk movie should not have to sit through a lecture about how the Hulk violates conservation of mass. Sure, the Hulk does gain hundreds of kilos of mass out of nowhere, but if you get rid of the (essentially magical) instant transformation of a meek and scrawny scientist into a giant green Incredible Hulk, then you're telling a different story. (Without the instant change he's just a steroid user with big weight fluctuations.)

So: from now on I expect every single moviemaker to use this resource. You no longer have an excuse.

The Fermi Paradox and Why It Matters

As a science fiction writer I have what may be called a professional interest in aliens. I read every popular science article or technical paper that comes to my attention about detecting or communicating with extraterrestrial civilizations. But I'm always a little surprised at how many people aren't interested in the subject. To me it seems incomprehensible: how can you not wonder about the possibility of life and intelligence elsewhere in the Universe?

One cannot argue about matters of taste. But one can argue about priorities, because I also happen to believe that studying the topic of extraterrestrial intelligence may be of tremendous importance for the survival of humanity here on Earth.

First, some background: the "Fermi Paradox" is the term we use to describe the puzzling lack of any sign of extraterrestrial intelligence. It's named for the physicist Enrico Fermi, and apparently came from a discussion he was having over lunch with some colleagues at Los Alamos during World War II. They'd been talking about the possibility of life on other worlds, and interstellar travel, and then on the way back to work after eating Fermi burst out with the question "Where are they?"

Of course, in the 1940s, the answer was actually pretty obvious and comforting: they're too far away to visit us. Beings on Mars or other planets of our Solar System might be able to build spaceships to reach Earth, but even then it was pretty obvious that neither planet had much in the way of life, let alone intelligence. As to civilizations on planets circling other stars, the distances were (and are) dauntingly vast. And at the time, the question of whether space travel was even possible still had yet to be answered.

In the decade following the war, radio telescopes began to search the skies, picking up the emissions of distant stars, nebular clouds, active galaxies, and even the echoes of the Big Bang. But one thing they didn't pick up were signals coming from alien civilizations. (At least, nothing that anyone has recognized as a signal in the past half-century.) In 1959 Philip Morrison and Giuseppe Cocconi published a paper discussing the possibility of detecting interstellar radio signals, doing some theoretical work on how it could best be accomplished.

Fermi's Paradox came roaring back. Even if interstellar travel remains forever impossible, it shouldn't be that hard to send messages to other star systems. Why hasn't someone broadcast a big hello to the Galaxy? Where are they?

And that's where the subject has remained for the past half-century. We've got more sensitive detectors, vastly better signal-processing methods, and many more radio telescopes. Private donors and governments have sponsored time on big instruments to listen for alien signals. There's even a dedicated SETI radio observatory, the Allen Telescope Array, searching the sky every day for signs of alien activity. The SETI@home project uses the donated computer time of millions of volunteers to process radiotelescope data in search of patterns which might indicate signals from other worlds. Nothing. Where are they?

There are reasons to be glad rather than disappointed at the lack of any sign of extraterrestrial intelligence. Back in 1998 economist and futurist Robin Hanson wrote an article about what he called "The Great Filter." Hanson's idea was that there must be some "filter" which stops most worlds from developing an advanced civilization capable of building radiotelescopes and broadcasting to the Galaxy. So far, we are the only civilization we know of to make it through the filter.

The big obstacle could be any of the terms in Frank Drake's famous "Drake Equation" to estimate the abundance of extraterrestrial civilizations (and thus calculate how far away they might be). Maybe planets with the right conditions are rare, maybe life doesn't form easily, maybe multicellular life is uncommon, maybe intelligence and tool-using are unlikely. But we made it past all those hurdles, so the Universe is ours! Right?

Maybe. Maybe not. See, for most of those potential filters, we don't really know the answers. Planet-finding telescopes like the Kepler mission have demonstrated that planets are extremely common, so the odds of finding worlds with the right conditions turn out to be pretty high. The history of life on Earth suggests it didn't take that long for life to evolve once the surface of our planet was no longer a sea of molten rock pounded by asteroids. (But, to be fair, we have no evidence that life has evolved elsewhere in the Solar System, so maybe Earth really did get lucky.) We have no way to tell if multicellular life or intelligence were flukes or inevitable.

And . . . there's still the possibility that the Great Filter isn't in our past at all. Maybe life evolves on lots of planets. Maybe complex organisms capable of using tools and communicating and inventing things are common in the Universe. And maybe something very bad tends to happen to them right around the time they become able to build radiotelescopes. That very bad thing must be something which alien minds as good as our own have been unable to foresee or prevent ��� even if they could come up with the idea of the Great Filter themselves. And maybe that very bad thing is about to happen to us! Isn't that a good enough reason to search for extraterrestrial life and civilizations? So we can figure out if something's about to make us extinct?

A Peeve

I've lately become rather irritated at seeing the helpful little notices on the paper napkin dispensers in coffeeshops and the more pretentious fast-food joints, asking patrons not to hog the napkins because "napkins = trees."

Grr.

Yes, paper napkins are made from wood pulp, and wood pulp is made from harvested trees. But: the idea that by not using napkins we are somehow Saving The Planet is idiocy.

Paper is made by paper mills, which buy their pulpwood from big forest-management companies, like Weyerhauser. Those companies own vast tracts of forest in the U.S. and Canada. Millions of acres. Harvesting trees is how forestry companies make money. So let's try a little thought experiment: suppose everyone in America decides that moral posturing is more important than clean hands, and consequently stops using paper napkins altogether. Paper prices collapse, and demand for pulpwood plummets.

What does Weyerhauser do with its millions of acres of trees? Continue to tend them lovingly, at considerable expense, despite the fact that those acres aren't generating as much revenue any more?

No. They would simply sell off those acres. (No sense in keeping capital tied up in worthless land, after all.) Nor will the buyers keep that land as forest, because they want some return on the money they've just used to buy it, and we've established that there's no demand for pulpwood. So the buyers will turn that land to other uses: farming, perhaps, or cattle-raising, or developing it as building lots. And for all those uses, the first thing they would do is cut down all the trees.

Congratulations, napkin-boycotters, you've just destroyed millions of acres of forest!

Now, I suspect most of those restaurants don't really give a tenth of a damn about the fate of the dear little trees. They're just trying to keep down their operating expenses and are using environmental guilt to keep the customers from taking big fistfuls of napkins. Wrapping yourself in the mantle of Saving The World when you're trying to save a few bucks verges on dishonesty, and I hate that.

Back to whatever you were doing.