How do I know that? All human inventions start out as a secret for a few, usually a group of individuals or the army. Because of its price, the risks it may imply, its complexity or a variety of reasons, every human invention takes time to be fully grasped by the masses. But eventually they all do. From air travel to lasers to plastic surgery to space tourism eventually the masses get to own, use and misuse each and every single human invention. Take my word on this: In less than a hundred years idiots crashing their spaceships into the Sun will be everyday news. Everything mankind has invented finds its way into the hands of the masses. Everything. As it has been proven, even big and expensive things like nuclear plants eventually end up in the hands of idiots.

And that is exactly how I know a time machine will never be invented. Because if a time machine was to be invented at some point in the future we would have seen it by now. Eventually and inevitably some idiot would get his or her hands on a time machine, travel into the past and be seen. And this would happen more than once. It would happen enough times as for us to accept the existence of time machines in the future as a fact. This should have already happened and should have been properly documented and it hasn’t. And it’s not because time machines will be invisible or something like that because it is a proven fact that eventually an idiot would fuck up. And be seen. More than once. So there you have it. That is how I know time machines will never exist.