How quickly a society advances in Tech Level can be a crucial element of a science fiction setting, especially one that proceeds from Earth’s present.

A rapid pace of technological change lets the GM add advanced technology to our own world without having to make many changes in present-day culture or international politics. Most cyberpunk worlds are examples of this. Rapid change suggests a dynamic society that is struggling to come to terms with the latest developments.

At the other extreme, many events common to science fiction settings require centuries or millennia: the establishment of large extraterrestrial populations, the rise of new civilizations or empires, or the terraforming of planets. If the GM wants to combine these long-range social and political developments with TL9 or TL10 equipment, it’s necessary to have a slow pace of technological change. This may take the form of a superscience technology (such as FTL travel) appearing at TL9, followed by a long period of slower technological growth.

The table below depicts five examples of TL progression: accelerated, fast, medium, slow, and retarded. Each has a set of “typical” start dates for TL9+ technologies, from the perspective of a present-day terrestrial human baseline in which TL8 began around 1980. These progressions can easily be adapted to other start dates for alien or alternatehistory cultures.

Accelerated progression is extremely fast, in keeping with some optimistic futurist or transhumanist speculations. At this speed, humans will reach TL12 before we can do much in the way of colonizing the universe. Perhaps we won’t even bother, if the “inner space” of nanotechnology and virtual reality provides everything we need.

Fast progression is an optimistic pace of development which recognizes that societies take some time to assimilate technologies. It assumes that the pace of invention begins to flag as certain fundamental physical limits are approached; it’s harder to play with atomic or subatomic technologies.

Medium progression could result from “bumps in the road” such as wars or disasters, or the influence of political movements or religious orthodoxy that impose a cautious approach to the sciences. This provides plenty of time for humanity to establish interstellar colonies or change society drastically without progressing beyond TL10.

Slow progression might be the result of multiple wars, resource exhaustion, or powerful anti-technology movements that put the brakes on progress. A slowly developing society may have organizations devoted to controlling “dangerous” technology.

Retarded progression usually stems from technological stagnation, often in conjunction with a Dark Age that causes a major decline or fall of civilization. This gives plenty of time for interstellar empires to be established without technology changing humanity beyond recognition, and pushes the development of TL12 civilization into the very far future.

Other options can also exist. A civilization could reach a particular TL plateau and then freeze or regress due to cataclysmic events or social changes. A society might be stymied by physical limits, such as one that develops underwater or on a world with few metals. Societies could also take a path where the main TL remained constant, but where steady progress was made in superscience, or even in psionics or magic.

The standard GURPS tech levels represent just one of many paths that describe how different technologies pace one another in development. The tech levels of the various items in this section should be treated simply as guidelines – a culture may develop some technologies more rapidly than others. This might result from accident, economics, a ban on research in certain areas, or the way the laws of physics work in that particular universe.

Apply the Split Tech Level rule (p. B511) as liberally as you wish to simulate a particular world or genre. For instance, in a “cyberpunk” society, computing, bionics, and biotechnology might be one or two TLs more advanced. In contrast, a “retro-tech” setting that mimics 1940s sci-fi might have computers frozen at TL6 but other technologies anywhere from TL9 to TL12. Any combination is possible! A few “alternative technology” concepts appear below. Feel free to use them, modify them, combine them, or create your own.

This is the “default” technology path – simply use every technology available at the assigned TL, whether it is radical tech, baseline, or superscience! In recent years, this has actually emerged as a dynamic science fiction sub-genre, sometimes called “the New Space Opera.”

Unrestricted tech can be challenging for the GM, especially at TL11 and TL12, due to the enormous range of possibilities and the array of resources it provides to adventurers. However, it allows for future worldbuilding on a grand scale, in which space opera and superscience meld with self-replication machines and nanotechnology to create baroque wonders and marvels.

In this path, technology is restricted to cautious extrapolations of present-day science. This type of setting may lack the sound and fury of space opera or radical hard SF, but it does bring a certain constancy to the campaign. If characters cannot rely on a technobabble device to produce a deus ex machina, the world may seem more real to the players – and more exciting as a result.

To create a conservative hard SF technology list, omit all new gadgets and technologies introduced after TL9. A conservative hard SF setting can still be specified as being TL10-12… if a TL9 gadget indicates it improves in some way at higher TLs, it still does so. For example, computers get their +2 Complexity per TL of introduction, but any new software or computer technology introduced at TL10+ is unavailable. This is a general principle; the GM is free to make whatever exceptions suit the setting.

A truly hard SF campaign will have no superscience at all, but a few carefully-chosen superscience inventions, such as a faster-than-light travel, may be added without changing the flavor too much.

Technology progression is usually medium or slow.

A radical hard SF setting emphasizes the transformational possibilities of technologies such as artificial intelligence, genetic engineering, nanofactories, robotics, selfreplicating machines, uploading, and mega-engineering. Humans (or other races) may evolve their own bodies or minds into barely recognizable configurations.

To create a radical hard SF technology path, set the campaign at TL10-12 but omit most or all superscience technology. As with conservative hard SF, a few examples of superscience may creep in, usually justified by a grand unified theory (GUT) that reconciles gravity and quantum physics.

Technology progression is usually medium, fast, or accelerated.

In this technology path, advances in cybernetics, medical science, and some computer technologies race ahead of other technologies. This is often combined with either an accelerated or fast TL progression. The increase in computer power is assumed to drive rapid developments in other fields, especially cybernetics, neural interfaces between mind and machine, and biotechnology, creating a “future shock” climate in which society is constantly struggling to adapt.

Cyberpunk worlds are usually TL8 to TL10. They have some or all of these features:

• Medical and biotech developments are strongly emphasized, and cybernetics or uploading may be one or two TLs more advanced than the general TL.

• Neural interfaces and sensies are common technologies, and may also be ahead of the general TL.

• Volitional AI is often present. Depending on the TL of the computer hardware, it may be available in mobile robots, or found only in the most powerful computer systems owned by large corporations and governments.

A few superscience elements often creep in. Many cyberpunk settings include monowire, neural disruptors, and downloading. However, even a cyberpunk game with no superscience can be cinematic in other respects; e.g., with the adoption of cinematic combat or computer hacking rules!

The standard tech progression assumes that dry molecular nanotechnology (the engineering of matter using nanomachines) is not mature until TL11. Some futurists don’t share this tame view. They predict a mature molecular nanotechnology will arrive within 30 to 50 years, creating a society that can build nearly anything for practically nothing.

Such a rapid nanotechnology revolution requires at least a TL9 background in chemistry and biotechnology. After it begins, spinoff factors will result in development in many other technologies, partly due to a vast increase in computing power and materials technology, and partly because nanomachines may be able to rapidly replicate and improve themselves.

It is simpler to assume that nanotechnology speeds up all technological progress than to pick and choose which technologies appear “early.” This is the accelerated TL progression, although even faster progress may be possible in some settings. A common Nanotech Revolution trope is the idea that super-intelligent computers, uploaded people, or other speedy nanotech entities will progress a TL every few years – or even every few months! The result may be a so-called “singularity” in which the world becomes unrecognizable. “Normal” humans might see a singularity as a bizarre apocalyptic horror setting. The super-minds could even evolve out of our reality completely, leaving behind dazed (and possibly altered) survivors in a transformed world.

A Nanotech Revolution is often a Radical Hard SF path – thus, a revolution in nanotech won’t quickly produce things like contragravity, force fields, or hand-held plasma guns. Just as often, however, the super-sapient entities produced may discover new physics that lead directly to the invention of superscience technologies at TL11+. For some notes on this, also see Superhuman Minds and the Singularity.

Matter transmission or force screens at TL9? Go ahead! Ultra-Tech assigns a default TL for most superscience technologies to give GMs a ready-to-use catalog and provide handy guidelines for gadgeteering. However, there is no reason superscience can’t appear earlier. Most such technologies require exotic breakthroughs (or breakdowns) in the laws of physics, but these breakthroughs can occur at any TL.

The classic emergent superscience example is the invention of a faster-than-light drive, star gate, interdimensional travel, or time machine at TL9. This allows humans like ourselves (rather than what we may transform into) to spread through the universe.

In a realistic setting, it might take at least a decade or two for a radical new theory to lead to real-world developments, but science fiction is full of instances where a theoretical breakthrough is quickly turned into functional hardware. By carefully adjusting the TL of superscience technologies, the GM can construct a society that resembles our own, then explore the changes a particular super-invention might bring.

In this path, inventions in biotechnology outpace inorganic chemistry and metallurgy. This is a common way to differentiate odd alien technologies from human ones, especially on metal-poor worlds, but it can also be applied to a particular human society. In such a culture, biochemical weapons, most biotechnological and medical technologies, wonder drugs, and non-cybernetic body modifications will appear one or more TLs in advance of everything else. The overall tech level is usually at least TL8, but the biotech TL is significantly higher.

Some High Biotech settings are fairly conservative, following slow or retarded progression paths. Nevertheless, if the biotech TL is set high enough (usually TL11+), biological analogs of other devices may also be available, at the GM’s option. For instance, automeds or infrared goggles might be genetically-engineered living creatures!

This idea can also be reversed. In a “low biotech” setting, the inventions and gadgets described above lag one or more TLs behind everything else. This could result from a moratorium on biotechnological research for religious or ethical reasons. A human colony world that has regressed to a primitive state might lag in biotechnology because human biology differs from all other life forms on the planet. This would keep experiments on animals from easily translating to humans.

A High Biotech setting can also lead to a Nanotech Revolution through the development of “wet” bio-nanotechnology. GMs will find GURPS Bio-Tech an invaluable resource for creating cultures that follow this technology path.

While science-fiction writers predicted robots, starships, and nuclear power, the invention of microchips and genetic engineering caught most by surprise. As a result, many famous science-fiction settings feature advanced physics and inferior electronics or biology. This isn’t bad: it can make for a more exciting space-opera campaign. Without the crutch of smart computers and advanced cybernetics, adventurers have to rely more on their own skills and less on those of their machines.

A retrotech setting is best defined as TL6 or TL7 plus whatever elements of emergent superscience the GM wishes to add. It doesn’t have to be space opera; if the superscience is tightly controlled (e.g., limited to star drives), it can feel like many 1940s and 1950s novels, which were hard SF at the time they were written. For example, a game modeled on 1950s military science fiction may feature mercenaries with steel helmets and assault rifles deployed in contragravity vehicles from starships, with space battles fought by autocannon and nuclear missiles rather than lasers. For a less retro feel, adding a limited set of nonsuperscience TL8-9 technologies – usually beam weapons, space drives, and energy or power supplies – will cover most space-opera scenarios.

Retrotech settings can have any TL progression. One common variation is to make them static or regressing. Such a civilization may still be recovering from or slipping into a dark age, in which science and engineering is no longer practiced. Most of society would have a base TL5-7 but still have access to a limited selection of TL8-12 devices (stardrives, blasters, giant robots, flying cities, etc.). New gadgets might still be built in automated robot factories, but no one really understands the principles behind them, and they are often operated by castes or guilds that may jealously guard what secrets they know.

In this technology path, physics and engineering have advanced dramatically (often to TL10-12), but developments that alter the way people think, modify the human body or brain, drastically extend lifespan, or threaten to replace humans with machines are retarded or suppressed. This may be due to ethical qualms, an accident of history, or a taboo resulting from past wars or disasters.

Without advances in these areas, tomorrow’s people won’t be much different from today’s, except for the quality of their technological toys. This sort of background is popular in supers and science-fiction settings, especially those rooted in the 1960s-1970s. If combined with a hard science path, it may even be realistic!

To maintain a “safe-tech” feel, remove the following technologies:

• Genetic engineering, except expensive immortality drugs reserved for a wealthy elite (these help perpetuate a conservative mindset).

• Neural interfaces and cybernetics, except for bionics intended to replace missing body parts.

• Molecular nanotechnology, especially nanofacs.

• Swarmbots.

• Volitional AI and mind emulations.

Safe-tech settings often de-emphasize networked computers (including today’s Internet) and augmented reality.

In a safe-tech setting, restricted technologies are usually possible, but haven’t been invented, or have been invented and rejected. Individual researchers (often of the “eccentric genius” or “mad scientist” gadgeteer type) and people working with alien technology may have produced examples of all the above technologies, as well as various types of superscience. However, these are unique prototypes, costing at least 100 times normal and defying easy reproduction.

Moreover, the lack of organized research in these areas means that breakthroughs tend to go out of control, harbor fatal flaws, or be stolen by criminals. This often results in the premature demise of the researchers and a further reinforcement of any bans.

Safe-tech cultures may “freeze” the social and political sciences, as well, since those fields are as likely to transform society as AI, nanotech, or cybertech. This often leads to a belief that “representative democracy (or democratic socialism, or feudal monarchy, or whatever) is the ultimate form of government.” Safe-tech cultures are full of monolithic planetary governments allied in tight confederations and empires with the power to impose bans on forbidden technology.

The enemies of a safe-tech culture are often those societies that embrace radical technology. Common adversaries include races of cyborgs, killer robots, single-sex clones, or genetically-engineered super-warriors.

Safe-tech civilizations normally follow a slow or retarded technological progression.

A psi-technology path is based around the understanding of the scientific basis of psi powers, and their widespread integration into society. It includes the development of psychotronics – devices that are intended to protect against, amplify, or enhance psi abilities, or which work using their principles.

However, the major development of psi-tech is not a gadget but a technique: the ability to locate, identify, train, and perhaps even genetically engineer people who possess psi powers. This may result in psi abilities becoming an open and accepted part of society, with telepathic detectives, judges, and psychologists, precognition solving crimes before they happen, doctors with healing powers, couriers (or burglars, or SWAT teams, or ordinary commuters) who teleport, and so on.

Societies may possess psychotronic superscience without following a psi-tech technology path, due to deliberate secrecy, the rarity of psi abilities, or popular distrust or fear of psionics. In such cases, psi-tech may be secretly controlled by private or government institutes, or defensive gadgets such as shield helmets and psionics might be the only available psionic technology.

Psi-tech paths may have any technology progression, but slow or retarded is common. A society that focuses on developing the mind may neglect other technologies.