Bonnie Chagneau-Ravoire is the greatest actress in the world, and I will fight anyone who disagrees.
02/22/2024
02/04/2024
Notes on Worldbuilding, Part 17: Aliens!
We've finally arrived at discussing actual intelligent extraterrestrial beings. I'm going to come at this concept from two directions in separate posts. This entry will discuss the science of alien beings — what they might be like, based on all the previous worldbuilding entries in this series. My next entry will look at aliens from a literary perspective, discussing what roles they can play in a story.
I can't list all the possible forms alien life may take. Look at the amazing variety of life on Earth, then realize that alien life will likely be even more diverse and strange. However, we can draw some basic ideas from biology and physics.
Size: The size range for intelligent beings is pretty big. What's the smallest brain capable of intelligence? How much does the brain-to-body ratio matter? How much does the structure of a brain matter? We're only just beginning to find out.
I think a human infant's brain is definitely big enough for intelligence (especially since we have seen very small adult humans with no sign of any impairment). Smaller than that we have only animals to guide us, and we have to figure out whether size or structure of a brain is more important for intelligence. Certainly some birds — ravens, crows, parrots — are disturbingly intelligent, with brains massing only 10-20 grams (while a human brain can be a hundred times bigger).
Let's call that the low end. We can also assume that a brain-to-body ratio of 1:20 (twice the proportions of a human brain) is the maximum possible, simply because brains are such energy hogs that an organism couldn't eat fast enough to support one any bigger. That gives us a minimum size for an intelligent being of 200 grams. That's the size of a large bird or a small monkey. With a more efficient brain organization, I can believe a creature like that would be capable of human-level intelligence.
At the upper end . . . well, that's a darn good question. Sperm whale brains are nearly 8 kilograms, and whales are famously intelligent animals. It's very easy to imagine whales with human-level intelligence — indeed, some people think they are as intelligent as humans. So I'm going to say there is no upper bound to how big an intelligent being can be, subject to the limits of physics.
Which we will now address. The largest land animals on Earth were the sauropod dinosaurs, some of which weighed in at close to 100 tons. On other worlds that would scale more or less with surface gravity. The square-cub law starts to bite hard when you get an organism of that size.
On land, that is. At sea, I don't think there is a limit to size, other than food supply. On an ocean world you could have marine grazers miles long, and some immense species might evolve intelligence, presumably via the route of language, social manipulation, and herding prey. If they were whale-like, it's hard to imagine they could develop much technology, but among the invertebrates there are plenty of marine animals with superb manipulating appendages.
Senses: Everybody knows that humans have five senses — seeing, hearing, smelling, tasting, and touching. Except that we actually have at least eight, since we can also sense temperature, feel the position and motions of our own bodies (proprioception), and detect gravity and acceleration (balance). But even on Earth there are other senses used by living things. Electric field sense, magnetic field sense, directional heat sense, and echolocation.
As near as I can tell, senses come in three main categories. Electromagnetic sense (vision, directional heat sense, and electric and magnetic fields); Physical sense (sound, infrasound, ultrasound, proprioception, touch, body temperature, balance, and echolocation); and Molecule detection (smell and taste). Because I have no patience for woo, we will ignore "psionic" senses.
Alien beings might add more senses in those categories. One can imagine alien beings using radio wave detection, radar, x-ray sensing, infrasonic or ultrasonic hearing, or maybe scent gradients to perceive the world around them.
It seems likely that sense organs will be located near the brain, and in most animals that would be near the front or top of the organism. Front because that's the way you move, and senses keep you from bumping into things or falling off cliffs. Top because it gives you more range. Chemical senses might concentrate near an organism's mouth (or other feeding organ) to detect whether things are good to eat.
Limbs: Humans have two arms and two legs, and most land vertebrates have the same four-limb arrangement. But that's mostly a historical accident: the first fish which adapted to life on land had four fins. They might just as well have had six, or eight. Invertebrates can have dozens. I strongly suspect that any alien organisms we encounter (or, more likely, exchange radio transmissions with) will have more limbs than we do. If you're building aliens, you can pick whatever number you like. Remember that in addition to limbs, there are also trunks, prehensile tails, prehensile mouthparts, tentacles, and tongues. One can imagine beings creating a technological civilization using any or all of them.
Skin: Life on Earth has a huge variety of outer coverings. Snails rely on a coating of mucus to protect their very thin skins. Humans have bare skin suitable for a hot climate. Birds have superb insulating feathers. Mammals have fur, almost as good. Fish have scales, reptiles have different scales, a few animals have armor plating — and that's not even considering all the ways plants garb themselves for protection. There's no reason alien beings can't have skin like tree bark or cactus rind.
An organism's outer covering protects against whatever the biggest local threats are — sunlight, cold, predators, parasites, dryness, and so on. Alien hides will likely be much the same.
Many organisms on Earth use their skins as billboards. Octopuses express some fairly complex emotions by changing the color of their skin. Other organisms shift color for camouflage, or to aid in temperature control.
Minds: This is the big one. This is really the only reason to go through the whole process of designing a planet, designing life, and designing intelligence. The whole process is aimed at producing an alien mind. A mind which does not think the way humans do. Otherwise, why not just write about humans? Alien minds are such an important topic that I'm going to put this one aside for my next post.
01/31/2024
Boskone 61!
On February 9-11 I'll be at the fabulous Westin Waterfront hotel in Boston for the 61st BOSKONE! The venerable New England convention is back again and I'll be part of it. Come on down and see some of the best writers in the U.S. talking about science fiction. And me. Here's my schedule:
Friday, February 9
4:00 p.m.: Harvesting Space for a Greener Earth — Can we save the Earth by developing space? Join me and a bunch of clever people to discuss the topic.
Saturday, February 10
5:30 p.m.: Alien Psychology: An Evolutionary Perspective — How does an alien species's biology affect the way they think? I have some thoughts, and we'll see what the rest of the panel thinks.
8:30 p.m.: Single-Biome Worlds in Science Fiction — Can there really be a "desert planet" or a "forest moon"? Is Earth just an "ocean planet" with a few other bits?
Sunday, February 11
11:30 a.m.: Writer's Blockbusting — Is "writer's block" real? What causes it? How to overcome it when you have to finish your book on time?
1:00 p.m.: Story Structures Other Than the Hero's Journey — Do all stories fit Joseph Campbell's archetypical template? Should they? I'll be moderating this and trying not to monopolize the panel because I have strong opinions about this.
01/21/2024
There Is No Fermi Paradox
The famous Fermi Paradox is one of the central concerns of research on the Search for Extra-Terrestrial Intelligence (SETI). Just to summarize quickly: we know of no good reason why technological civilizations can't emerge on other worlds in our Galaxy, but we see no signs of any. Paradox!
"Where is everybody?" Enrico Fermi asked plaintively.
But it's not a paradox. We see no signs of extraterrestrial civilizations because we've barely looked.
The Milky Way contains 100 to 400 billion stars (and the fact that the possible range is that large should be suggestive — there's a lot of things we don't know). How many of those stars have we searched for signs of advanced civilizations?
Not many. To spot a civilization like our own, you couldn't just glance at the Solar System with a radio telescope and instantly detect some old sitcom broadcast. That's not how it works. You'd have to watch over a long period — months or years. You'd have to detect the faint radio emissions and link them to the orbit of Earth around the Sun and Earth's own rotation.
According to Jill Tarter's index at technosearch.seti.org, the biggest search so far covered 290,000 targets. The SERENDIP survey looked at 30 percent of the sky, but that was all piggybacked observations on other astronomers' observing sessions, so very few of those examined the same target repeatedly or over a long period. The Breakthrough Listen project aims to study 1 million objects over the next decade.
That would be . . . one percent of the Galaxy. Maybe less. At this rate it'll take millennia to finish the job.
These are all good and valuable projects, but they're woefully limited. The real solution to the Fermi Paradox is a very simple one: we don't know enough. We don't know if there are stars wrapped in alien Dyson Sphere megastructures. We don't know if there are tiny, heavily Doppler-shifted point sources in interstellar space burning the exact color of deuterium fusion rocket exhaust. We don't know if there are stars with rosettes of co-orbital worlds in their habitable zones, all with identical atmospheres and surface temperatures. We don't know!
I do expect the pace of SETI to pick up as techniques are refined and infrastructure expands. There's also the heartening fact that the "giggle factor" of searching for "little green men" among the stars seems to be waning. After decades of after-hours bootleg research, SETI is finally getting serious support. All this means that it probably won't take a thousand years to search the other 99 percent of stars in our Galaxy. Maybe not even a hundred years.
What then? What happens when we have made a serious effort to search the sky?
Well, the results can be generalized into four cases.
Case 1: Nothing! It's 2124 and we've given the Galaxy a thorough going over and found no sign of intelligence other than our own. Maybe signs of life here and there, but no radio signals, no energy emissions, no artificial structures. Apparently we really are the only minds in the Galaxy.
This could go either way. It might cause a turning away from space exploration because nobody really likes to consider awful, infinite emptiness. Maybe over time some eccentric tycoons will fund colony projects on the Moon or Mars, and maybe the resources of near-Earth space will attract robot miners, but the bulk of humanity will stay on one planet for the foreseeable future. Some people may find this idea appealing, but I don't. To my mind, it's one small step from that to suicide.
Or perhaps the certainty that there's nobody out there would stimulate expansionist ideals among humanity. Unlike exploration and colonization projects on Earth, this time there's nobody to get hurt or displaced. Manifest Destiny on a cosmic scale! The Universe is our sandbox and we can play with it as much as we like! It's something to hope for, I suppose.
And either way I expect a hard core of diehards will insist that we just haven't searched enough. This will become an increasingly hard line to sell, but people are persistent, and those lonely SETI researchers will keep listening . . . to silence.
Case 2: We Are Not Alone, Barely. Our searches turn up one or two civilizations. They're thousands of light-years away and are modest in scale. This would naturally spur interest in the idea of communicating with them, even though it may take centuries to even get a reply. In effect, alien intelligence would be a cool science fact but little more than that. Space exploration and astronomy will still be driven by commercial concerns, national pride, and scientific curiosity, probably at about the same levels of funding as today. Crackpots will finally have a name to put on their imaginary alien friends, but otherwise life goes on as before.
The biggest winners in this case will be SETI and astrobiology researchers, because finally they'll have some data to work with! Humans can learn about alien life and intelligence in relative safety.
Case 3: They're Everywhere! Turns out we picked the wrong 1 percent to search at first. Once you learn the trick, finding alien civilizations is easy. Disturbingly easy. There's scores of them in the Milky Way, and some of those civilizations are big.
As with Case 1, the response could go in one of two ways. Either humanity will try to hide, masking and muting our emissions, putting strict (and probably un-enforceable) restrictions on transmissions to the stars, and generally doing our best to avoid attracting the attention of beings who can move stars around.
Or our insatiable curiosity will prevail, and we'll listen and learn and eventually try to make contact. Whatever happens, this is a turning point in human civilization. It's going to affect government policy, education, everything. The night sky will never look the same again.
SETI — and planetary protection — will become national security priorities. Radiotelescopes will sprout like mushrooms, both on Earth and the far side of the Moon. Whether we're hiding or trying to join the interstellar club, learning about alien civilizations, figuring out their goals and especially how close they are will be of capital importance.
Case 4: They're Here! The crackpots were right. They were here all along. Somebody finds a probe on the Moon, or the seabottom, or on a near-Earth asteroid. They've been watching us, maybe for decades or maybe for millennia.
The take-away is simple: they're real, they know we're here, and they can reach us. As with the above scenario, expect a massive push to discover as much as possible, this time without the option of trying to stay hidden.
Ironically, the big losers in this latter case would be the UFO crackpots. Because now defense agencies, universities, governments, and international organizations will be taking the concept of life beyond Earth very seriously. There will be a lot of research, done rigorously and systematically. No more blurry photos, no more woo. Astrobiology and SETI will become as serious, well-funded, and no-nonsense as nuclear power or genetics research.
Which will it be? My money's on Case 2. I don't think we're alone, but I think it's a lot harder to create and maintain a technological civilization than astronomers think it is. Our views are biased, because we live on a world where it did happen, so of course it looks practically inevitable. Whichever proves to be the truth . . . we'll see! And I hope it's sooner rather than later.
01/09/2024
Notes on Worldbuilding Part 16: Alien Reproduction
All living things reproduce. Organisms on Earth have evolved a dizzying array of reproductive habits and anatomy. I'm just going to look at the very basics in this post, and next time we'll look at how reproduction might affect the mentality and society of alien beings.
Strategies: Biologists have identified two basic reproductive "strategies" for living things on Earth — though of course there are plenty of variations within the broad outlines. Basically one can classifty species as "K-strategy" or "r-strategy" in reproduction. (And yes, the K is capitalized but the r is lower case.)
K strategists put a great deal of effort into supplying and supporting their offspring, trying to guarantee their survival and thereby maximize reproductive success. Obviously this emphasis on "quality" means K strategists tend to have fewer young. Elephants, humans, and orcas are K strategists, with immense parental and social investment in the care of young, and typically give birth to only one or a few offspring at a time.
Conversely, r strategists emphasize quantity. They have large numbers of young — sometimes extremely large numbers — and as long as one or two survive to adulthood, it counts as success. Maple trees, lobsters, and shad all have enormous numbers of offspring. Trees release thousands of airborne seeds, lobsters fill the water with gametes and hope they find each other, and shad lay thousands of eggs at a time. Once they've released their young into the world . . . they're on their own.
Obviously there are intermediary or relative cases. Compared to most fish, mammals are obsessive about caring for their young, but among the mammals you have humans and elephants devoting years to raising a single offspring while possums have a dozen every year.
Sex: The vast majority of organisms on Earth reproduce very simply. They split in half and the two new entities go their separate ways.
Asexual reproduction is universal among single-celled organism but it shows up in complex multicellular creatures as well. Often it can persist alongside sexual reproduction in the same organism. Many plants, for instance, can not only send out seeds or create fruit, but also bud off clones of themselves from roots or branches.
Sexual reproduction requires two parents (and there are reasons why two is likely to be the maximum) who combine their genes to create a distinct new organism. They don't ever have to see each other, but their gametes do. Sexual reproduction is slightly more difficult to arrange than asexual, but the greater genetic diversity resulting from sex means that when conditions change the species can evolve to adapt faster.
Sexual reproduction has two main modes. In external fertilization, organisms release their gametes into the outside environment and hope that complementary gametes will find them. As one might expect, this is typically part of an r strategy approach, since there isn't really any way for a parent to care for its young when it has no idea where they might be or whether they even exist.
Conversely, internal fertilization needs the parent organisms to actually come into physical contact. This has benefits and drawbacks: mating is more of a "sure thing" than just spewing pollen into the air and hoping it finds its mark, but of course this means an organism must locate a potential mate and secure its cooperation.
As I mentioned, there is a staggering variety of mating arrangements among animals, and there is no way I can summarize them all in a blog post.
Males produce "cheaper" or less energy-intensive gametes, though typically their gametes are more mobile. The goal is to maximize the number of chances to get a successful fertilization.
Females produce gametes which have a support system — either in the form of a yolk sac for eggs, nourishment from her own body for live-bearing females, or other mechanisms. Their gametes have a better chance to gestate successfully.
Some species — like snails — are hermaphrodites, with both male and female gametes. They mate and both get fertilized eggs. Others shift from male to female depending on conditions.
Gestation: Again, there is tremendous variation, but how the young develop can be divided into live-bearing and egg-laying.
Live-bearing organisms gestate their young within the mother's body. This is a comparatively K type method, though some mothers can support dozens of young at a time. But live-bearing represents a huge investment in the survival of the offspring, and is often accompanied by some degree of post-natal care by the parent.
Egg-laying organisms (and, if you squint, seed-bearing plants) release the young in a container of some kind, along with a supply of nutrient which can support the young through development until hatching. As one would expect, it lends itself to r strategy approaches, although there are plenty of counter-examples of egg-layers who lavish care on their young.
Care: Humans are probably the kings of giving care to young, keeping ours around for a decade or more before they're ready to live on their own. Most other mammals spend only a year or two at it. Even so, caring for one's young is a large investment of resources but pays off with a higher survival rate. Often this requires the development of complex social structures so that members of a pack or herd can help feed and look out for the young ones.
Hives: The social insects (and a few other species) have come up with a method that combines the massive birth rate of an r-strategy organism with the high survival rate of a K-strategy species. Essentially one or more "queens" does nothing but reproduce, while her sterile sisters and daughters work to get food, defend the hive, and care for the young. Since they're all related, the workers' genes are carried on via their fertile sisters. I'm listing it as a "parenthood" strategy rather than a social system, because it's pretty hard-wired. You're not going to see ants leaving their hive and going off to raise a family alone.
As I keep repeating, this just scratches the surface, and a little research into the variety of life on Earth will teach you about much weirder reproductive systems than anything you can imagine on your own.
01/04/2024
The Zoo Hypothesis: Objections
Recently the magisterial Centauri Dreams 'blog ran a post by Paul Gilster about the "Copernican Principle" and how it conflicts with the observed facts about life in the Universe. (Short version: the Copernican Principle says Earth should be an average world, but if that's the case, why don't we see more signs of life elsewhere? If life is rare, then Earth isn't average after all.)
In the course of this discussion, Mr. Gilster touched on the famous "Zoo Hypothesis" — the notion that the reason we don't see signs of extraterrestrial life or civilizations is that someone is keeping them all away from us. He traced the idea back to Olaf Stapledon, which doesn't surprise me because almost every idea about space or life in the Universe can be traced back to Olaf Stapledon.
That started me thinking about why I've never really believed in the Zoo Hypothesis, so I've decided to share my ideas here. I want to be pretty rigorous about this, so I'm going to define my terms first and then go on to discuss the conclusions one can draw from them and why they basically refute the whole hypothesis.
Core Premise: Some active agency (hereafter "the Zookeepers") is stopping any expansionist interstellar civilizations from expanding into the region containing our Solar System.
Second Premise: The goal of the Zookeepers is protective. They want to keep infant civilizations or lifebearing worlds from being swallowed up by "grabby" aliens. If they just wanted to stop any civilizations from expanding, or even existing, that's the "Dark Forest Hypothesis" or possibly the "Berserker Hypothesis." I'm not talking about that here, although some of the topics I'm going to touch on today may be relevant to both of those.
Third Premise: The Zookeepers must have some means of preventing other civilizations from entering the "Zoo" region, which means they (or at least their agents) must surround the whole area. They may have a whole civilization enveloping the Zoo, or just a picket sphere of guard posts, possibly automated.
Fourth Premise: The entire Zoo project is not the primary purpose of the Zookeeper civilization. The majority of their resources are devoted to other things.
Fifth Premise: We will assume the Zookeepers have no magic powers. They cannot travel or communicate faster than light, or do anything else which contradicts our understanding of natural laws. We will grant them effectively infinite resources and arbitrarily advanced engineering, since presumably no civilization would undertake something like the Zoo project unless they are able to actually accomplish it.
Okay, with those premises, what can we deduce?
First, we know that we can see the Zookeepers!
Consider: the Zookeepers exist at a distance R1 from Earth. They have created a Zoo region for us with a radius R2, and R2 is less than R1. In order to surround the Zoo, the Zookeepers must send some kind of spacecraft at no more than the speed of light, to a distance of R1+R2 from their homeworld. Since R1+R2 is obviously greater than R1, and the ships can't outpace light, that means that we have to be able to see light from the Zookeeper home system which was emitted after they became capable of launching interstellar spaceships. Possibly a long time after, depending on how long the project has been in operation.
From Premises Four and Five we deduce that you can't hide a star system which contains a civilization capable of large-scale interstellar operations, which the Zookeepers are by definition. They're going to be emitting heat, EM radiation, laser light, all the spoor of a Kardashev Type I or higher civilization. And the farther away they are, the more they're going to be emitting because they need to be bigger and more energy-rich in order to have greater reach.
This gives us one important lesson: if the goal of a Zoo is to keep the civilizations inside from even knowing of the existence of other civilizations, the whole thing is impossible. You can't have a Zoo without Zookeepers, and the inhabitants of the Zoo will detect them.
Second, we're almost certainly alone in our Zoo.
Consider: the Zookeepers wish to protect the inhabitants (Second Premise). They can't protect individual star systems, because that would leave the Zoo inhabitants' home system surrounded by interlopers from grabby civilizations, and the Zookeepers' guard posts would be right at the edge of the protected system and thus in plain view. No, the Zoo needs to be big, incorporating multiple star systems. Its radius R2 must be on the order of tens of lightyears.
But, if a Zoo contains more than one lifebearing world, then one of those planets might produce a civilization capable of building its own starships, and therefore could become grabby and colonize the other lifebearing worlds, defeating the purpose of the Zoo. Consequently each Zoo will be centered on a lifebearing world, but will include only one. (If life is so common that nearly every star system has a good chance of harboring it, then the Zoo project is impossible.)
Third, a Zoo needs to be visible!
If you're going to exclude other civilizations from a particular region of the Galaxy, you have to let them know. Shooting relativistic projectiles or giant laser beams at incoming starships is a very ham-fisted way of communicating "keep out!" — and it runs the risk of convincing the grabby civilization that you're shooting at to start shooting back. And if they're grabby and control a lot of star systems, that's going to be a lot of shooting.
Therefore, a Zoo has to be marked. It needs beacons around it, transmitting to anyone within range that "this volume of space is off limits." These beacons need to be visible at ranges approximating R2, so that would-be interlopers have plenty of advance warning and no shooting is required.
It may well be possible to make a particular Zoo's warning beacons invisible to any newborn civilizations inside it — but you can't hide any other Zoo spaces from them! As noted in my second conclusion, above, it's likely that each Zoo contains only one lifebearing world, so that there could be a large number of discrete Zoos (depending on how powerful the Zookeepers are). We should see clusters of beacons marking other Zoo regions.
Fourth and finally, the Zookeeper civilization, or whatever sub-unit of it is responsible for the Zoo project, needs to be incredibly stable and persistent. Even with near-lightspeed travel, they're going to be sending out starships on voyages measured in centuries, protecting planets over time scales rivaling geological periods in length. All it takes is one shift in attitude among the Zookeepers and all the worlds they've been protecting could get colonized. We know they can reach the target worlds because they can reach well beyond them, so it's only their moral fiber and devotion to the cause that keeps the Zoo in existence.
Yeah, I don't believe those are strong enough, either.
So I think the Zoo Hypothesis is kind of self-refuting. If we don't see aliens because we're in a Zoo, then . . . why don't we see the Zookeepers? Why don't we see the boundaries of the Zoo? Far from being a solution to the Fermi Paradox I think it's even more paradoxical: we don't see aliens because there are aliens all around us!
Nope. I don't buy it. I don't buy the Dark Forest or the Berserker Hypothesis either, for similar reasons. They all require large, visible alien civilizations to explain why we haven't observed any alien civilizations. There must be some other reason.
Update (January 5): While I was writing this, apparently Paul Gilster was having his own thoughts on the subject, which you can see here.
12/28/2023
12/25/2023
Christmas Dinner Bragging
The menu for this year's Christmas dinner (with photos when I remembered to take them):
Smoked Whitefish Pickled Herring in Sour Cream Vermont Camembert
Cremant de Loire
Prosciutto-Wrapped Shrimp
Braised Beef Brisket Sauteed Potatoes Roasted Brussels Sprouts
Medoc
Poached Salmon Mixed Green Salad
Christmas Pudding Ice Cream
11/26/2023
Notes on Time Travel Stories
Time travel has been a fixture of science fiction ever since a young Englishman named H.G. Wells wrote his first novel, The Time Machine. Wells wasn't the first person to write about time jumps — Mark Twain did it in A Connecticut Yankee in King Arthur's Court — but before Wells it was always treated as fantasy. Twain's hero is cast back in time by a blow to the head, then sent back to his own time by magic. (Thus giving the excessively literal-minded reader the chance to say "it was all just a dream." I hate that trope.)
Wells moved it into the realm of science because physicists like Einstein were starting to consider time as another dimension of spacetime. As Wells's nameless protagonist The Time Traveller puts it, you can move around in three dimensions with steamships or balloons, so why not move around in four, letting you go backward or forward in time? So time travel gained some new plausibility thanks to science.
Lately I've been thinking about time travel stories, thanks to this recent Ars Technica article about the best time travel films. I realized that "time travel stories" actually combines two distinct sub-genres, or sub-sub-genres.
The first type, and by far the most common, is exactly what H.G. Wells himself did in The Time Machine: someone uses a time machine to travel to the past or future. They get in their car ("time machine") and drive to History, do stuff there, and then drive home again. Instead of a car one can use a train, an elevator, a door, or whatever. The point is that The Past or The Future is treated as a place, where one can have adventures, meet famous dead people, make dreadful warnings about social trends, or whatever.
Authors writing this kind of time travel story tend to put significant limits on how the time travel works, because the whole point is to go back or forward in time and have adventures. If the characters can just get back in the time machine and replay their exploits over and over until they get the right result, it's not very suspenseful or exciting.
The second kind of time travel stories are those which are actually about the mechanics of time travel itself. Examples of this variety include Heinlein's "All You Zombies" or "By His Bootstraps," novels like Gerrold's The Man Who Folded Himself, or films like Primer. In this kind of story, the authors get to play with causality, closed time-loops, paradoxes, and so on.
As one might expect, the second type is considerably harder to write, and the ship-in-a-bottle difficulty of pulling it off at all tends to make the actual stories more clever than good.
I wonder if we should come up with names to distinguish the two types of time travel stories. Maybe call the first variety "Time Voyages" and the second "Time Twister" stories? Suggestions are welcome.
Recent Comments