[FOM] Historical query (on the very idea of a formalized theory)

[Peter Smith]

Church in his Intro. to Math. Logic (pp. 50 - 51) very clearly spells it 
out that, for a properly defined "logistic system", the definition of a wff 
has to be effective, the specification of the axioms has to be effective, 
and it has to be effective what counts as a proof by the rules of 
inference.

I was wondering: at what point between did people become explicit and clear 
about this sort of effectiveness requirement on a properly formalized 
theory?

-- 
Dr Peter Smith: Faculty of Philosophy, University of Cambridge
www.logicbook.net | www.godelbook.net
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http://www.phil.cam.ac.uk/teaching_staff/Smith/LaTeX/   
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