Any wizard bright enough to survive for five minutes was also bright enough to realize that if there was any power in demonology, then it lay with the demons. Using it for your own purposes would be like trying to beat mice to death with a rattlesnake.
Interpretation
Power drawn from dangerous sources can lead to self-destruction.
In this quote, Terry Pratchett reflects on the folly of attempting to control or utilize dark powers for personal gain. He likens the effort to a dangerous and ultimately futile struggle, highlighting that those who understand the true nature of such powers recognize their inherent risks and the potential for self-harm when meddling with them.
In practice
In a lecture on ethics in magic, one might quote this to emphasize the risks of using dark powers.
And then Jack chopped down what was the world's last beanstalk, adding murder and ecological terrorism to the theft, enticement, and trespass charges already mentioned, and all the giant's children didn't have a daddy anymore. But he got away with it and lived happily ever after, without so much as a guilty twinge about what he had done...which proves that you can be excused for just about anything if you are a hero, because no one asks inconvenient questions.
They've got something they do it with, I think it's called a mocracy, and it means everyone in the whole country can say who the new Tyrant is. One man ... one vet. ... Everyone has ... the vet. Except for women, of course. And children. And criminals. And slaves. And stupid people. And people of foreign extraction. And people disapproved of for, er, various reasons. And lots of other people. But everyone apart from them. It's a very enlightened civilization.
Geography is just physics slowed down, with a couple of trees stuck in it.
You can't trample infidels when you're a tortoise. I mean, all you could do is give them a meaningful look.
Any fool could be a witch with a runic knife, but it took skill to be one with an apple corer.
People look down on stuff like geography and meteorology, and not only because they're standing on one and being soaked by the other. They don't look quite like real science. But geography is only physics slowed down and with a few trees stuck on it, and meteorology is full of excitingly fashionable chaos and complexity. And summer isn't a time. It's a place as well. Summer is a moving creature and likes to go south for the winter.
Making no mistakes is what establishes the certainty of victory, for it means conquering an enemy that is already defeated.
Remember that the good angels do what they can to preserve men from sin and obtain God's honor. But they do not lose courage when men fail.
They that will not be counseled, cannot be helped. If you do not hear reason she will rap you on the knuckles.
Inner freedom is not guided by our efforts; it comes from seeing what is true.
People have writer's block not because they can't write, but because they despair of writing eloquently.
Prefer punishment to disgraceful gain; for the one is painful but once, but the other for one's whole life.
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