Physics and aerospace
The Aquarium Problem
A fish concludes correctly that leaving the water would kill it, and incorrectly that no other ocean exists.
UnknownThe glass is not necessarily the edge of reality. It is only the edge of the evidence.
What we actually know
The fish's reasoning is sound. Its evidence is real. Every measurement it can make inside the tank supports the conclusion that the boundary of the glass is the boundary of survivable reality. It has never had access to the street outside, or to the ocean across it.
Where the extrapolation begins
Humanity may be making equally reasonable deductions from an equally restricted environment. Our physics is derived entirely from experiments performed inside one universe, at one range of energies, by one species, using instruments built from local matter. That does not make the conclusions wrong — the fish is right about the air — but it does make the scope of the conclusions uncertain.
What the novel invents
Humility does not prove another ocean is there. It only reminds us that the glass is not necessarily the edge of reality. The novel takes no position on what is outside the tank. It only insists that something got in.
Questions to think about
- — Which of our physical laws are about reality, and which are about our position in it?
- — Design an experiment a fish could run that would hint at the ocean across the street.
Where to read next
- — Observation selection effects and anthropic reasoning
- — History of assumed cosmic boundaries later dissolved (crystal spheres, the Milky Way as the universe)
Continue in the archive