Whatever goals the AI has, it will certainly be better at achieving them if it can stay alive. And it will be more likely to stay alive if there are no humans around to interfere. Now you might say, why don't we just hardcode in a goal to the AI like "solve aging, and also don't hurt anyone"? And ensure that the AI's method of achieving its goals won't have terrible unintended consequences? Oh, and the AI's goals can't change? This is called the AI control problem, and nobody's been able to solve it yet. It's hard to come up with good goals for the AI. It's hard to translate those goals into math. It's hard to prevent the AI from misinterpreting or modifying its own goals. It's hard to work on AI safety when you don't know what the first strong AI will look like. It's hard to prove with 99.999% certainty that your safety measures will work when you can't test them.
Things will not turn out okay if the first organization to develop strong AI is not extremely concerned about AI risk, because the default is to get AI control wrong, the same way the default is for planets to not support life.
My counterpoint to the risks of more limited AI is that limited AI doesn't sound as scary when you rename it statistical software, and probably won't have effects much larger in magnitude than the effects of all other kinds of technology combined. Limited AI already does make militaries more effective, but most of the problem comes from the fact that these militaries exist, not from the AI. It's hard for me to imagine an AI carrying out a military operation without much human intervention that wouldn't pose a control problem.
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