"...You know, I haven't thought about it before," he says, "but I actually think I do. I mean, technology isn't just about planting a flag in the laws of physics - it's not about what you can do, it's about what you want to do and what you need to do, and people's wants and needs don't stay static forever. I don't think there's some kind of ceiling on what we can do with technology, and even if there is, if I ever reach the point where I literally can't think of anything else I want to invent because all of the cool shit exists already, I will be totally willing to retire and play with my toys for the rest of ever."