It was just the first random idea that came to mind. But the general point is that when thinking about "interface", we often don't even consider that the inter

It was just the first random idea that came to mind. But the general point is that when thinking about "interface", we often don't even consider that the interface could be made of physical things and instead implicitly assume pixels on screen. The idea that you could interact with a system not using video is practically unthinkable. Victor's point is that we can't invent what we can't imagine, so it's important to always have visions that seem unattainable and not give in to accepthing things as they are.