The Flea & The Acrobat

"Science is neat, but I'm afraid it's not very forgiving"



"Picture... an acrobat... standing on a tightrope. Now, the tightrope is our dimension. And our dimension has rules. You can move forwards, or backwards. But, what if... right next to our acrobat, there is a flea? Now, the flea can also travel back and forth, just like the acrobat. Right? Right. Here's where things get really interesting. The flea can also travel this way... along the side of the rope. He can even go... underneath the rope. Upside down. Exactly. But we're not the flea, we're the acrobat. In this metaphor, yes, we're the acrobat. So we can't go upside down? No."