If you have big ideas and even bigger dreams, chances are you’ll have naysayers not far behind. And while it’s important to be able to respect creative criticism and understand what’s viable as well as the risks your idea entails, it’s equally good to know that some of the biggest, most revolutionary ideas in history were shut down by some pretty prominent people back in the day. Here are five predictions about big inventions and ideas that missed the mark by a mile and then some.