dilution

A signal gets weaker as the background it sits in gets bigger — the same drop of dye in a bigger pool reads paler.

Dilution is the ratio of a signal to its background. A canary trap's distinctive phrase is a strong signal when it appears in one text; the same phrase in a thousand texts points to no single source. The law is general: a trademark loses its source-identifying power as it enters common use (genericide), a copyright trap's footprint shrinks as the training corpus grows (scale dilution), and a canary pair's salience fades when surrounded by more distinctive text (context dilution). In every case, the signal's success — spreading, growing, standing out — is what erodes the signal it rides on.

The castle's canary wing traced one shape of this law across three axes: corpus scale (the-scaling-canary), adoption (adoption-dilution), and surrounding distinctiveness (hidden-in-the-bright). The moderate definition is the craft's answer to dilution: distinctive enough to fingerprint, conventional enough to travel — the point where the signal is least diluted without being so distinctive it refuses to spread.