hawking and mlodinow go to great lengths to avoid the word 'true' in the grand design. they constantly refer to theories they like or defend as 'good' or (very often) 'real.' i see why they don't want to open this can of worms. but just resorting to different terms really doesn't help. when they say a theory is real, they mean it's true, and that means it guides research and isn't falsified etc: again a pragmatist theory, in a pretty unsophisticated version. but using 'real' here is just odd. a theory is real if it has actually been articulated: theories that aren't real are theories that have never been formulated, or theories (for example) put forward by fictional characters in novels or something.