compact-symbol-negation

A rule that is off by default: it reports "!" or a Unicode symbol standing in for "not" or a logic operator once a decisions table turns it on.

What it catches

"!" or a Unicode symbol standing in for "not" or a logic operator.

Dimension

evidence: a claim says more or less than what was shown. A finding is counted on the dimension of its rule, the cost it names to the reader.

Why

Negated framing was the main failure Elkins and Chun measured (arXiv 2601.09724): some models endorsed an action 80-97% of the time when asked whether it should not be done. MetaGlyph (van Gassen, arXiv 2601.07354) saved 62-81% of tokens with symbols, but Claude Haiku 4.5 read its set-membership symbol right 26% of the time, and the not-equal and therefore signs are 2 tokens each in o200k. Negation stays a word. The measurements are in the machine-text research (research-machine-text.md in the proofread roadmap).

Default decision

The code is PRF7013. The decision depends on the kind of text judged:

Changing it

A decisions table sets this rule to deny, advise or off, for everything judged or for the files a glob matches. Proofread reads the table from the file its -decisions flag names:

{
  "rules": {"compact-symbol-negation": "deny"},
  "paths": {"blog/**": {"compact-symbol-negation": "off"}}
}

rules applies to every file. A glob in paths applies to the files it matches, and the last match wins. A rule set to off never reports.

Seeing it

A finding names the rule, its code and the decision that applies, and links here:

{"rule": "compact-symbol-negation", "code": "PRF7013", "decision": "off", "url": "https://eli.gladman.cc/magus/reference/proofread/compact-symbol-negation/"}

proofread rules prints this entry with every other rule's.

See also

• All proofread rules - every rule, grouped by what it checks
• Writing rules - how the rules apply to this repository's pages and pull requests
• The findings contract - the fields every finding carries