Hey Vsauce, Michael here

Hey, Vsauce. Michael here. The dog that played Toto in The Wizard of Oz was credited as Toto, but in reality the dog's name was Terry. And when Terry died in 1945 her owner and trainer Carl Spitz buried her on his ranch in Los Angeles. But in 1958 the Ventura Highway was constructed right through Terry's grave. Her remains were disturbed and have never been found. Fifty-three years later a memorial was erected in Hollywood Forever Cemetery in her honor but because she isn't burried there, the memorial is not a grave. It's what's known as a cenotaph, an empty tomb. I was reminded of Toto's cenotaph when I saw the cenotaph of Philopappos, atop the Hill of the Muses in Athens. You see, I was recently in Greece talking about YouTube with YouTube creators. The all seen eye of Guy came along and we visited the Acropolis, a Lion Gate - nearly a thousand years older than the Acropolis. The earliest known analog computer. Plenty of beautiful cats and I even took a selfie in Delphi. I've seen all of these things and how old they were, it made me wonder how will we be remembered. How will future archaeologists react to the ruins of today's society they find thousands of years from now. Will they do a good job piecing it together? Will anything about you in particular be remembered? And, for that matter, how do we even know that the past really happened? Not just the way we think it happened, but it all. Seriously, can you prove that the universe wasn't created last Thursday? That everything - every person, every memory you have, every photo you've taken didn't just pop in into existence last week or five minutes ago? Last Thursdayism is the belief that the universe was created last Thursday. It doesn't have actual followers or rituals but proving it wrong is impossible. Not because the universe actually was created last Thursday but because Last Thursdayism is not also falsifiable. It cannot be shown to be false. In the evidence you bring up against it can be explained away as part of the everything that was created last Thursday. Many people believe that in order for a theory and explanation to be scientific it must be possible to refute it, to prove it wrong, to test it. So, instead, Last Thursdayism falls into the domain of philosophy, where luckily there are razors - little rules of thumb that help shave off unlikely explanations. The most famous is Occam's Razor. When faced with the choice between explanations, choose the one that requires diffused assumptions. Occam's Razor can shave off last Thursdayism because it requires fewer assumptions to believe that, say, this beehive tomb was constructed way back in the Bronze Age and that I just visited it later than it does to believe that the tomb, my memories of it and this footage of me inside it just happen to coincidentally pop into existence at the same time last Thursday. One of my favourite philosophical razors cuts off so much stuff it's not even called a razor.