 This work is significant with respect to the subsequent development of computability theory for at least three reasons. First, it contains a informal description of what we now call the primitive recursive functions. Second, it can be regarded as the first place where recursive definability is linked to effective computability (see also Skolem 1946).  And third, it demonstrates that a wide range of functions and relations are primitive recursive in a manner which anticipates  Gödel’s (1931) use of primitive recursion for the arithmetization of syntax.   