Hawking and Mlodinow appeal to the idea of evolution and natural selection in which people who draw the right conclusions survive better so that as we evolve we get closer to the right conclusion. However, they question whether it is still the case now. With regard to evolution it is interesting that the abstract mathematics that underlies our physics seems to have little survival value.
A further question then for current research is how did chaos and disorder that occurred immediately after the Big Bang become transformed into an ordered “smooth” universe, where at any time one part of the universe looks much the same as any other part. Distant stars and galaxies are distributed much the same everywhere and resemble the local ones in terms of their compositions and motions.
However a quantum vacuum is not absolutely nothing, but is a source of fluctuating energy. Also the particles are generally virtual particles, that is theoretical particles whose existence is not clear, being possibly just theoretical constructs. In any case we still have to account for the existence of the quantum vacuum. Another approach used by some is to simply redefine “nothing.” However, we cannot really define nothing in the first place except as the absence of something.