The Preliminary
Four movements, four rounds each. Sixteen rounds that measure how fast you read a symbol, how long a sequence you hold, what you can build from a description, and what you can prove from a set of rules.
A provisional Δ, and an account of how it was arrived at — which faculty gated it, which round each movement gave way at, and what tightened at that round. The account is the point. The number without it would be a horoscope.
It is not your Standing Δ. That is set only by the monthly Diagnostic, which runs for forty-five minutes and does not stop until you do.
Symbol–Digit Substitution · ~2 min
Forward and Reversed Recall · ~2 min
Construction from Description · ~3 min
Conditional Logic · ~4 min
16 rounds · about eleven minutes · no account needed
Δ is an institution-internal score. It measures a Fellow’s performance on this institution’s assessments relative to other Fellows. It is not an IQ test, not a medical assessment, and not a diagnosis. It is a training benchmark, like a 1-rep max or a recital programme.