I can't let this one slip by. I'm watching Through the Wormhole with Morgan Freeman. He's introducing a philosopher who has an interesting theory and I just can't let it stand as described. The man's name is Jan Westerhoff.
He contends that when you wake up, you may well be simply waking up into yet another dream. He offers as a mathematical proof, well, indicator of possibility, the following:
This is a significant chance that we are dreaming right now. Most people spend eight hours asleep and 16 hours awake in a 24-hour period. 20% of this sleep time is REM sleep, or rapid eye movement sleep. This means that any given individual is dreaming for about 20% of those eight hours. Therefore, we are in a dream state approximately 1.6 hours out of every day. He concludes that this means we have a 1 in 10 chance of being asleep and dreaming at any given moment of any given day, including right now.
Ignoring the fundamental problem which somehow seems not to occur to him, that if we are asleep, none of the data he assumes to be factual can be trusted; I couldn't help but consider another set of numbers.
The age of the universe, as far as we know, is 13.7 billion years. Let us assume the human lifespan at 100 years, not an unreasonable assumption for the upcoming generation. Ignoring the future, which cannot be accurately estimated since it could end with the heat death of the universe or could extend into infinity if there is a multiverse, this means that a human lifespan is only 1/137,000,000 of the age of the universe. Using Dr. Westerhoff's logic, we can therefore conclude that the possibility that any single person is alive at this moment in time is nonexistent for all practical purposes.
I conclude that we should ignore the rest of what he had to say, since he is clearly dead. It is not wise to listen to the dead. Biblically, this is considered to be a terrible sin. If you don't believe me, consider the case of the Witch of Endor. I also don't think it's practical from a scientific viewpoint. But it doesn't matter anyway, since according to his logic, all the rest of us are also almost certainly dead.
Thus, I finally conclude that it is unwise for philosophers to delve into areas best left to mathematicians.
If you're not familiar with the Bible, I assume that the term Witch of Endor strikes you as rather Hobbit like. Nevertheless, it is biblical. Look it up.
Yes, I know. He could also be not born yet. But I'm not a Mormon, so I'm not even gonna go there.
I'm a lot more philosopher than mathematician and a lot more poet than philosopher, therefore you're welcome to check my math. Please send me any necessary corrections. To any mathematicians out there, I sincerely apologize for trespassing into your territory. In my own defense, I point out that I didn't start it, that other guy did!
Well, back to Dr. Westerhoff...