Information theory: redundancy, error-correction, and compression

A poem's rhythm, a tally stick's notches, and a beacon-lighting relay have nothing in common on the surface -- except that all three, this page argues, are quietly doing the same engineering job an error-correcting code does. Claude Shannon's information theory gives that job a vocabulary: redundancy that lets a garbled message be caught and fixed, a checksum that flags tampering, compression that packs meaning into as few symbols as possible, a channel with a hard ceiling on what it can carry. This lens tests whether pre-print writing systems carry exactly that kind of extra, non-decorative structure: poetic meter functioning as built-in error correction, the Hebrew Bible's Masoretic apparatus -- the marginal notes and letter-counts that fixed its exact wording -- working as a checksum for over a thousand years, and the notches on a tally stick acting as anti-fraud bits.

Notation as compression and Pāṇini as compression both treat a formal system -- musical notation, Sanskrit grammar -- as a compression scheme, asking whether it packs meaning into fewer symbols than a naive encoding would need. Formulas as error correction and The tune is the meter police test whether poetic formula and meter really do function as error-correcting redundancy, catching a reciter's slip before it corrupts the text. Tally-stick checksums and Khipu redundancy look at two very different physical media -- a notched tally stick, a knotted khipu cord used for Andean record-keeping -- for the same engineering signature: extra structure that exists only to guard against error, not to carry content.