[jacquesm]

I think in most cases the onus to prove that there is a baby is on the one making the claim that this is so. Besides the impossibility of proving a negative.

[mannykannot]

Speculation, by definition, lacks proof. Where would we be without speculation? Speculation has to range wider than proof for there to be any intellectual progress.

Galileo, whose name is invoked frequently in these discussions, speculated broadly and was often wrong.