In “The Hitchhiker’s Guide to the Galaxy” by Douglas Adams, the haughty supercomputer Deep Thought is asked whether he can find the answer to the ultimate question concerning life, the universe and everything. He replies that, yes, he can do it, but it’s tricky and he’ll have to think about it. When asked how long it will take him he replies, “Seven-and-a-half million years. I told you I’d have to think about it.”