Physics Levels and Other Nonsense

Posted: 2024-03-20
Word Count: 854
Tags: gurps rpg

Table of Contents

Having always been fascinated by the idea of alternate worlds, I once worked out parameters other than thaumic levels to characterize different worlds (or different locations within a world). Sadly I seem to have misplaced those notes, but here I recreate “Physics Levels”, “Psi Levels”, and “Superscience Levels”.

Physics Levels

Long before I encountered The Strange I had an idea: not only do alternate worlds vary by magic quantity and quality but by the physical laws that govern them. As far as I remember, I used the GURPS Mana Levels as a model. Below are the labels and the highest Progress Levels or Tech Levels in various systems.

Phy Label Max GURPS TL Max d20 PL Max Trav TL Description
U Unlimited 12+ 9 ??? science indistinguishable from magic
VH Very High 11^ 8 15 superscience and space opera
H High 10 6 8.5 anything not impossible with known physics
N Normal 8.5 5 8 anything possible with known physics
L Low 4.5 3 3 macroscopic mechanics and chemistry only
VL Very Low 2.5 2 1 Aristotelian physics only
0 None 0 0 0 no physics, just magic and/or psionics

Note that “.5” indicates that some advances from the next higher tech level are possible, as long as they match the description.

“High Physics” may include advancements in cybernetics, biotech, AI, space ships and even nanotech but not FTL, antigravity, energy from nothing, and comic-book genetic engineering. It’s speculative but hard science.

Likewise “Low Physics” will not support radio, electronics, quantum mechanics, or any scientific discovery beyond, say, 1750. It may support gunpowder and other chemical discoveries, and maybe even certain forms of medicine from later eras, but nothing involving organic chemistry or models of the atom. Most science in these worlds is trial and error with a bit of luck.

“Very Low Physics” lacks even the amenities of the medieval and early modern eras. Science as we know it doesn’t exist; “natural philosophy” observes the natural world but is singularly unsuccessful in making significant changes to it. Technology has at best a few successes: engineering, Roman concrete, maybe non-lethal medicine. In general these worlds are fantasy settings where magic or psionics, if presence, take the place of anything beyond simple technology.

A device that requires higher technology than the local physics will simply stop working. “Very Low Physics” and “No Physics” worlds, mercifully rare, can get very weird.

Psi Levels

Psi levels will depend heavily on the rules for psionics, much as Mana Levels depend heavily on the rules for magic. For example, if psi powers require a percentile skill roll to activate and the expenditure of Psi points, we might define Psi Levels as follows:

Psi Label Activation (d100 /2d6) Point Cost
U Unlimited +100% / +6 none
VH Very High +50% / +4 x1/5
H High +20% / +2 x1/2
N Normal +0% / +0 x1
L Low -20% / -2 x2
VL Very Low -50% / -4 x5
N None

In an article I sketched out a different way to characterize Psi Levels:

  1. No psychic ability at all […]
  2. Luck, ESP, and other vague talents that alter probabilities or give flashes of insight unpredictably … usually ignored or explained away.
  3. Classic sci-fi psi: telepathy, ESP, precognition, minor telekinesis.
  4. Cinematic psi: major telekinesis, pyrokinesis, teleportation, psychic healing, mind hacking, clouding men’s minds.
  5. Superpowers: metapsychic powers from U.S. and Japanese comic books.

This approach is more qualitative, and there are borderline cases. For example, are Steven King’s Carrie or Firestarter more “classic sci-fi” or “cinematic”? I’d argue for cinematic, but classic science fiction novels include teleportation and mind probes.

Still, if each level is covered by a different system entirely, the borders remain fairly clear. For example:

  1. No rules save maybe for conjuring tricks, e.g. sleight of hand, applied psychology.

  2. A feat, advantage, boon, etc. to sense something or bend the rules a bit, with all information provided at the GM’s discretion. e.g. GURPS Advantages like Luck1, Intuition2, and Danger Sense 3.

  3. A system for low level “space magic” modeled after those old SF stories, e.g. Classic Traveller’s/Cepheus’ psionics system, or for a pulpier feel the Trinity Continuum: Adventure RPG.

  4. A flexible system for high level powers with no inherent limits, e.g. GURPS’s Psionic Powers supplement, the old Psi World RPG, or the Trinity Continuum: Aeon RPG.

  5. A general system of superpowers, e.g. the Hero System game Champions, GURPS’s Super Powers supplement, or the Trinity Continuum: Aberrant RPG.

Super Science Levels

Without a framework for “super science” – technology that breaks established theories and their constraints – it’s hard to come up with a gradiated scale. For now we’ll use a very coarse-grained one:

Super Science Label Description
U Unlimited All superscience allowed
H High Superscience cannot use discredited theories (e.g. no Aether)
N Normal Superscience is at least superficially plausible.
L Low Superscience must be possible albeit ahead of its time.
N None No superscience allowed

  1. Character’s player gets a free reroll once per hour. ↩︎

  2. Character can make an IQ check to come to a non-obvious conclusion. ↩︎

  3. Character gets a Perception check to sense an impending threat despite no obvious signs. ↩︎