if something can be done in principle, there is no good reason why it should not be done although it has not yet been done and there may be some difficulties原则上;理论上
In principle there is nothing that a human can do that a machine might not be able to do one day.原则上,总会有一天,凡是人能做的事,机器就能做。
in general but not in detail大体上;基本上
They have agreed to the proposal in principle but we still have to negotiate the terms.他们已基本同意了这项提议,但我们还得磋商各项条款。
I agree with you in principle, but we'll need to discuss the details.我原则上同意你的意见,但是我们需要讨论一下细节问题。