The days may seem long, but life itself is rather short. As Bill Nye the Science Guy explains, an average human life will span about 30,000 days. That may seem long, but consider that the typical professional football stadium holds twice as many seats. If you sat in a new seat each day of your life, you would not visit even half of the seats in the sport stadium. In order to make the most of our lives, we would do well to meditate on our own mortality as a way to understand just how precious and limited our existence is.

Josh: Hey Bill. Do you ever think about your mortality? Does it ever bother you to think that one day you just won't exist? I know you're not religious but do you think anything happens when we die or is it just over, no thoughts, nothing like that? And if given the choice to live longer in an artificial body would you take that or not? Thanks. Bye.

Bill Nye: What a question. That was Josh? Josh, fabulous question. Yes I think about mortality continually man. I won't say constantly but everyday. So I'd like to just give you something to think about. If you lived to be 82 and seven weeks, depends on leap years as to the exact number of weeks, you get 30,000 days on earth, 30,000. When you're in kindergarten 30,000 sounds like a lot, almost an unimaginably big number. When you are my age, I'm 61, you start to see that 30,000 really isn't that many. And to show you it's not that many I encourage you to imagine a National Football League stadium. They typically hold way more than 70,000 people, certainly way more than 60,000 people. So imagine sitting in a different seat every day of your life and watching your life take place down on the field, imagine this. Sit in a different seat everyday. Day-to-day it looks about the same right? But with 30,000 you don't get halfway around, halfway around and you're dead. It sucks man. So it's why it's important to do your best to live your life as best as you can every day. This doesn't mean you become a hedonist and just have a joyride everyday, you're working too big goals but no one appreciate that everybody is going to die. I have never met anyone who is not going to die. I've never met anyone who's of a certain age who is not already dead. It sucks.

Now here's the evidence for why I don't believe in an afterlife. It would be a fine thing if I could have the capabilities athletically that I had when I was say 23 with the life experience and intellect that I have right now. That would be fantastic and then live forever, I say bring it on. But my beloved grandmother, who was brilliant, didn't have that happen. She faded away losing her faculties as she went. People my age have a lot of grandparents and parents who are not as sharp, certainly not as athletically capable or physically capable as they were when they were younger. And so watching ourselves die is to me overwhelming evidence that there is no life after death. There doesn't seem to be any reason to think that when you die you go back to your optimum age at your optimum athletic ability and your optimum intellectual sharpness. And if it turns out that that's true, that you do die and have all this intellectual sharpness and athletic ability, cool. Bring it on. That will be great, but what would you do differently? What would you do differently if you knew for sure that you were going to be immortal when you died somehow?

Would you start committing crimes? Would you jump off a cliff so that you can hurry to your immortality optimal state? I just don't think so. Instead, the finite length of our life is what drives us, it's what makes us go and it's what makes you try to accomplish things or decide to have kids or not have kids or decided to live in another country on another continent or not or decide how to invest your money or what you're going to do with your resources. All this is driven by the limited length of life we have. So furthermore, if evolution is in fact how the world works, and it absolutely sure seems to be from my point of view, one of the fundamental things about evolution that is so troubling is this whole idea of survival of the fittest. That's really a 19th century usage, a British usage of that expression fit-est. It doesn't mean that you're able to do the most weightlifting or run the fastest 1500 meters or something, it means you fit in the best. And the troubling, troubling consequence of this is you don't have to be perfect or super person, you just have to be good enough from an evolutionary standpoint. You just have to be good enough to pass your genes on. After that evolution, if it were an entity, doesn't really care about you man. You had your kids, your genes are passed on and you expire, you lose your faculties as you run out of steam and that's just how it is.

Evolution, certain diseases catch up with you, certain auto immune problems show up, certain viruses and bacteria, parasites get you. Nature doesn't care. You were good enough. And so I encourage you to live your life as best you can everyday. And as far as putting my brain in an electronic receptacle for all time it sounds great, but I will valuate it on a case-by-case basis. Do you want to be stuck in an Apple product the rest of your life or do you want to be stuck in a Microsoft product? That's a tough call. I'm sure books will be written. We'll see. Great question. Carry on.