> as lemmas

1909 Philos. Rev. 18 199 This identity-formula, which is thus exemplified in the simplest and most rudimentary form of valuation, the existential judgment, is further traced throughout the whole series of systems of valuation which furnish the body of our scientific, artistic, ethical, religious, and philosophical thought.

1965 B. Mates Elem. Logic ix. 146 It will be useful to introduce a couple of obvious conventions for writing identity-formulas.

2008 P. Ulrich Integrative Econ. Ethics v. 170 ‘I reckon, therefore I am’ (to play on Descartes famous dictum) is the identity formula of the otherwise identityless ‘homo oeconomicus’.