I believe, say, before I begin, it doesn’t make any difference what number you choose for this. I happen to be prejudiced against mind readers from experience in nature, in physics. I don’t see, if I believe that man is made out of atoms and if I know all of the—most of the-ways atoms interact with each other, any direct way in which the machinations in the mind can affect the ball. So from other experience and general knowledge, I have a strong prejudice against mind readers. Million to one.

Now we begin. The mind reader says it’s going to be black. It’s black. The mind reader says it’s going to be red. It’s red. Do I believe in mind readers? No. It could happen. The mind reader says it’s going to be black. It’s black. The mind reader says it’s going to be red. It’s red. Sweat. I’m about to learn something. This continues, let us suppose, for ten times. Now it’s possible by chance that that happened ten times, but the odds are a thousand to one against it. Therefore, I now have to conclude that the odds that a mind reader is really doing it are a thousand to one that he’s not a mind reader still, but it was a million to one before. But if I get ten more, you see, he’ll convince me. Not quite. One must always allow for alternative theories. There is another theory that I should have mentioned before. As we went up to the roulette table, I must have thought in my mind of the possibility that there is collusion between the so-called mind reader and the people at the table. That’s possible. Although this fellow doesn’t look like he’s got any contact with the Flamingo Club, so I suspect that the odds are a hundred to one against that. However, after he has run ten times favorable, since I was so prejudiced against mind reading, I conclude it’s collusion. Ten to one. That it’s collusion rather than accident, I mean, is ten to one, but rather more likely collusion than not is still 10,000 to one. How is he ever going to prove he’s a mind reader to me if I still have this terrible prejudice and now I claim it’s collusion? Well, we can make another test. We can go to another club.

We can make other tests. I can buy dice. And we can sit in a room and try it. We can keep on going and get rid of all the alternative theories. It will not do any good for that mind reader to stand in front of that particular roulette table ad infinitum. He can predict the result, but I only conclude it is collusion.

But he still has an opportunity to prove he’s a mind reader by doing other things. Now suppose that we go to another club, and it works, and another one and it works. I buy dice and it works. I take him home and I build a roulette wheel; it works. What do I conclude? I conclude he is a mind reader. And that’s the way, but not certainty, of course. I have certain odds. After all these experiences I conclude he really was a mind reader, with some odds. And now, as new experiences grow, I may discover that there’s a way of blowing through the corner of your mouth unseen, and so on. And when I discover that, the odds shift again, and the uncertainties always remain. But for a long time it is possible to conclude, by a number of tests, that mind reading really exists. If it does, I get extremely excited, because I didn’t expect it before. I learned something that I did not know, and as a physicist would love to investigate it as a phenomenon of nature. Does it depend upon how far he is from the ball? What about if you put sheets of glass or paper or other materials in between? That’s the way all of these things have been worked out, what magnetism is, what electricity is. And what mind reading is would also be ana-lyzable by doing enough experiments.

Anyway, there is an example of how to deal with uncertainty and how to look at something scientifically. To be prejudiced against mind reading a million to one does not mean that you can never be convinced that a man is a mind reader. The only way that you can never be convinced that a man is a mind reader is one of two things: If you are limited to a finite number of experiments, and he won’t let you do any more, or if you are infinitely prejudiced at the beginning that it’s absolutely impossible.

Now, another example of a test of truth, so to speak, that works in the sciences that would probably work in other fields to some extent is that if something is true, really so, if you continue observations and improve the effectiveness of the observations, the effects stand out more obviously. Not less obviously. That is, if there is something really there, and you can’t see good because the glass is foggy, and you polish the glass and look clearer, then it’s more obvious that it’s there, not less.

I give an example. A professor, I think somewhere in Virginia, has done a lot of experiments for a number of years on the subject of mental telepathy, the same kind of stuff as mind reading. In his early experiments the game was to have a set of cards with various designs on them (you probably know all this, because they sold the cards and people used to play this game), and you would guess whether it’s a circle or a triangle and so on while someone else was thinking about it. You would sit and not see the card, and he would see the card and think about the card and you’d guess what it was. And in the beginning of these researches, he found very remarkable effects. He found people who would guess ten to fifteen of the cards correctly, when it should be on the average only five. More even than that. There were some who would come very close to a hundred percent in going through all the cards. Excellent mind readers.

A number of people pointed out a set of criticisms. One thing, for example, is that he didn’t count all the cases that didn’t work. And he just took the few that did, and then you can’t do statistics anymore. And then there were a large number of apparent clues by which signals inadvertently, or advertently, were being transmitted from one to the other.

Various criticisms of the techniques and the statistical methods were made by people. The technique was therefore improved. The result was that, although five cards should be the average, it averaged about six and a half cards over a large number of tests. Never did he get anything like ten or fifteen or twenty-five cards. Therefore, the phenomenon is that the first experiments are wrong. The second experiments proved that the phenomenon observed in the first experiment was nonexistent. The fact that we have six and a half instead of five on the average now brings up a new possibility, that there is such a thing as mental telepathy, but at a much lower level. It’s a different idea, because, if the thing was really there before, having improved the methods of experiment, the phenomenon would still be there. It would still be fifteen cards. Why is it down to six and a half? Because the technique improved. Now it still is that the six and a half is a little bit higher than the average of statistics, and various people criticized it more subtly and noticed a Couple of other slight effects which might account for the results. It turned out that people would get tired during the tests, according to the professor. The evidence showed that they were getting a little bit lower on the average number of agreements. Well, if you take out the cases that are low, the laws of statistics don’t work, and the average is a little higher than the five, and so on. So if the man was tired, the last two or three were thrown away. Things of this nature were improved still further. The results were that mental telepathy still exists, but this time at 5.1 on the average, and therefore all the experiments which indicated 6.5 were false. Now what about the five?… Well, we can go on forever, but the point is that there are always errors in experiments that are subtle and unknown. But the reason that I do not believe that the researchers in mental telepathy have led to a demonstration of its existence is that as the techniques were improved, the phenomenon got weaker. In short, the later experiments in every case disproved all the results of the former experiments. If remembered that way, then you can appreciate the situation.