 Azzouni describes his ‘version of formalism’ (Azzouni, 2004: 105) as one in which ordinary mathematical proofs ‘indicate’ formal derivations. The indication relation is left rather open: Azzouni does not claim that the indicated derivations all belong to a single formal system; rather ordinary proofs can indicate derivations from a ‘family’ of formal derivations. However, the indicated derivations, Azzouni says need not exist; certainly concrete tokens of them need not exist in the same period as the informal proofs which indicate them. Proofs in ancient Greek geometry indicate 21st century or later derivations. They may never, in fact, exist—they may be too long ever to be written down (Azzouni, 2006: 154) though these non-existent proofs are supposed to explain the consensus among mathematicians about which informal proofs are correct! In later work Azzouni seems to retreat from this (or any) brand of formalism: