Brand is basically saying that a god exists because he wants it to be so - regardless of the fact that there is no evidence to support his belief.
He justifies his belief by saying that science is good at explaining 'what' but doesn't explain 'why', which somehow entitles him to supply his own 'why' and claim it as true.
He justifies his belief by saying that science is good at explaining 'what' but doesn't explain 'why', which somehow entitles him to supply his own 'why' and claim it as true.