Hawking and Hartle understood the kind of wave function that would have physical and cosmological relevance and then chose possible universes for inclusion in their summing procedure in accord with selection criteria that would ensure that kind of wave function. Similarly, Vilenkin knew the boundary conditions he would need to choose, and the assumptions about allowable universes he would need to make, to ensure the construction of a relevant wave function. Both the selection criteria in Dawkins’s biological simulation and the physical selection criteria (of the quantum cosmologists) were
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