Stephen Wolfram in his blog:
For me personally, the vision that became Wolfram|Alpha has a very long history. I first imagined creating something like it more than 47 years ago, when I was about 12 years old. Over the years, I built some powerful tools—most importantly the core of what’s now Wolfram Language. But it was only after some discoveries I made in basic science in the 1990s that I felt emboldened to actually try building what’s now Wolfram|Alpha.
It was—and still is—a daunting project. To take all areas of systematic knowledge and make them computable. To make it so that any question that can in principle be answered from knowledge accumulated by our civilization can actually be answered, immediately and automatically.
Leibniz had talked about something like this 350 years ago; Turing 70 years ago. But while science fiction (think the Star Trek computer) had imagined it, and AI research had set it as a key goal, 50 years of actual work on question-answering had failed to deliver. And I didn’t know for sure if we were in the right decade—or even the right century—to be able to build what I wanted.