The level ladder
The enginealso: levels · level codes · node · node levels · reader-facing namesThe ten kinds of node in a decomposition tree, from the master question down to the executable experiment.
Q0 is the master question. M_G is a goal pillar. RA is a requirement atom. DOM is a domain finding. S is a seed question. L3 is a gap question. IH is a hypothesis. L4 is a discriminating question. L5 is a mechanistic sub-question. L6 is an idea, a proposed investigation, the executable test with its system, intervention, meter and threshold. The engine names nodes by these codes; the site renders each with its reader-facing name and keeps the code as a chip.