Pratchett has written more than 30 novels about the likes of Corporal Carrot, Granny Weatherwax and Gaspode the Wonder Dog.

BBC: Pratchett novels go to Hollywood

But I wonder if the Dog theory can be applied to exchange trade funds with better results.

FORBES: Dogs Of The ETFs

Yet his anger at what he sees as the cluelessness of the governing class hasn't dampened his zest for life, or his sense of wonder at such transformations as the tatty dog track of his youth giving way to a resplendent Olympic stadium.

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