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原則上;理論上
In principle there is nothing that a human can do that a machine might not be able to do one day.原則上,總會有一天,凡是人能做的事,機器就能做。
in general but not in detail大體上;基本上
They have agreed to the proposal in principle but we still have to negotiate the terms.他們已基本同意了這項提議,但我們還得磋商各項條款。
I agree with you in principle, but we'll need to discuss the details.我原則上同意你的意見,但是我們需要討論一下細節問題。