Sun 17 Jan 2010
“Did you say the stars were worlds, Tess?”
“All like ours?”
“I don’t know, but I think so. They sometimes seem to be like the apples on our stubbard-tree. Most of them splendid and sound – a few blighted.”
“Which do we live on – a splendid one or a blighted one?”
“A blighted one.”
— Thomas Hardy (Tess of the D’Urbervilles)
Do you feel lucky to be here? How lucky do you have to be in order to require a special explanation of that luck? Some philosophers and scientists have argued that the very improbability of our being here, of the universe being constructed so as to allow the conditions for intelligent life, requires a special explanation, a God, or intelligent designer, behind the original conditions of the universe. Part of the impetus for such arguments comes from an awareness of how the development of the universe depends upon certain variables that are not derived from anything else, but which are traced back to certain original conditions within a primordial singularity or big bang. Supposedly, when one looks at the number of such variables and the possible values they could have taken, the possibility of a universe arising in which one gets things such as stars and planets, or any kind of matter of the sort we know, is so small as to defy understanding. Roger Penrose has calculated the probability of a universe that might contain the preconditions for life as 1 in 10 raised to the 10123 power. (That is 10 followed by more zeroes than there are particles in the universe.) According to this, all of us have pulled out the one lucky ticket out of gazillion-zillion-zillion losers in the cosmic lottery. Do you feel that lucky?
The philosopher, Daniel Dennett, has suggested that this type of line of reasoning makes a simple logical mistake, jumping from a very obvious restriction on the type of things we can expect to observe to a very dubious conclusion about the origin of those conditions. Physicists sometimes call the starting point and ending points of this jump the Weak Anthropic Principle and the Strong Anthropic Principle, respectively. The Weak Anthropic Principle is sometimes stated as a recognition of the observation biases we find due to the limited range of possibilities we can observe. Just as we can only expect to see, with our naked eye, the small range of electro-magnetic phenomena that are visible to us; so we can only expect to observe the small range of possible configurations of the universe that are compatible with our existence. If we exist, then the conditions necessary for our existence must obtain. Stated this way, this seems just about as obvious as anything could be. If I am here, then none of the things that could have prevented it have happened: I haven’t been shot, run over by a car, had a heart attack, or any of the other things that could have prevented me from being here. I am not particularly lucky in having avoided these things. That I have avoided them doesn’t require any special explanation. Of course, if I am here, then none of these things happened, but there is no special reason that they didn’t; they might have. The Strong Anthropic Principle suggests that these original conditions, that the universe is capable of supporting intelligent life, are somehow necessary, and it is this necessity that requires special explanation. If, as I was walking over to my office, a car attempted to run over me and mysteriously swerved at the last moment; if no matter how determined the attempts to take my life, they were somehow thwarted (as in a Pink Panther film), then I would be lucky in a way that requires explanation. The question is whether the origin of the universe is like this kind of case. Dennett merely points out that this does not at all follow from the weak version of the principle.
William Lane Craig has suggested that the origin of the universe is, indeed, more like this kind of case, comparing it to a firing squad that misses mysteriously. If 25 marksmen with perfectly functioning rifles all train their guns on a man at 50 paces, it is vastly improbable that they all should miss. If one of them typically misses such a shot only 1 in a 100 times, the probability of them all missing is 1 in 10025 or 1050. One would not expect a miss if they fired once a second from the beginning of the universe 1017 seconds ago until now. If such a thing happened, we would most certainly require a special explanation, such as that they all disobeyed orders and missed on purpose. And, of course, this improbability is small compared to the super-super-astronomical improbability of the original conditions of the current universe according to calculations such as Penrose’s.
The real question is whether the assumptions that allows us to draw inferences in cases such as these apply to the original conditions of the universe. When we calculate probabilities we draw inferences from the formal structure of a situation based upon certain assumptions, chief of which are (1) The choices between the different possibilities are completely random; and (2) We are considering the probability of one unique instance, specifiable in advance. We cannot know to any degree of certainty that either of these conditions obtain in the case of the origins of the universe. Let us consider the second assumption first. When a meteor makes it through the atmosphere, it is certain to hit somewhere; though of all the innumerable places it could hit, it is improbable that it will hit me. After the fact, if we find the unlucky person that it hits, even though they are only one of the millions of people it could have hit, the fact that it hit them requires no special explanation; it had to hit someone after all. When we reach into a hopper full of 1000 white balls, each with a number, and pull out number 367, the odds of pulling that number out were 1 in 1000. Yet surely, I would be silly to thank my lucky stars for pulling off a 1 in 1000 shot. Each of the other indistinguishable possibilities was also a 1 in a 1000 shot, and there were 1000 of them, hence it was certain that I would get some number or other. If, on the other hand, there were one special number, specified in advance, and I was able to choose that and win the lottery, this would seem to require some special explanation. Again, this assumes that this instance is unique. If I repeated my attempt 1000 times, it would be even money that I would get the lucky number at least once. Imagine that in 999 other rooms, unknown to me, there are 999 other identical hoppers with other people choosing 1 of the 1000 balls. I may feel lucky, but the odds were that one of us would pick the lucky ball. Dennett, along with many other thinkers, has pointed out that if this universe is not unique, if innumerable other multiverses are playing the cosmic lottery, odds are that someone had to win, so it is not surprising that we find that we did. But, in this case, the very nature of the singularity from which the universe arose seems to prevent us from knowing whether this roll of the dice is unique or not.
Likewise, we have no way of knowing if the choices between the various different values of the constants in Penrose’s calculation are equally likely and taken at random. It turns out that 81 times 114,839 is equal to 9301959, the exact date of my birth. Is this a lucky stroke? Are the gods of mathematics preordaining the universe to my amusement? After all, there are 10 million other 7 digit numbers that could be the answer to that problem. But just as 2 times 2 couldn’t be anything but 4, so we may think there is nothing else that could be the answer to this particular multiplication problem. Are the different possible values of the cosmic constants equally likely? Could there be something that constrains them or renders them necessary, of which we cannot be aware? Again the very fact that the causal chains, which provide us knowledge, can reach back no farther than the Big Bang, renders it impossible, in principle, to answer these questions. In such cases, the conditions that allow us to draw inferences from probabilities, simply cannot be known to apply.
I am not enthusiastic about the Anthropic Principle as evidence for God’s existence, but I do like to think about it, since it reveals interesting things about how we think about chance and Providence. If this universe is the result of an intelligent agency, the most interesting thing about it will not be its existence, no matter how unlikely: Note that in the above cases there was nothing interesting, requiring special explanation, about me being the one being hit by the meteor or being the one who wins the ball lottery if 1000 others are playing as well. There was nothing about me, specifiable in advance, that made me unique. Yet to me it makes all the difference. There have been about 106 billion human lives in this unlikely universe, of which about 7 billion are going on now, about 5.8 percent. Of these, 80% live in abject poverty, with an even larger proportion of those who lived in the past, leading even more miserable lives, subject to the worst kinds of pains, fears, and misfortunes. So only approximately 5 of 100 of the humans ever to have lived has ever been as fortunate as you. As we sit here at our computers, full of belly, warm of foot, healthy and well contented, we can see that there is nothing about us that could have been specified in advance that renders us more deserving than any of the other human souls to inhabit this unlikely universe, sole supporter of intelligent life, the winner of the cosmic lottery. Yet here we are. Do you feel lucky?
 The Emperor’s New Mind, 344.
 Darwin’s Dangerous Idea, Ch. 7.
 “The Teleological Argument and the Anthropic Principle,” http://www.leaderu.com/offices/billcraig/docs/teleo.html#text16 .
 0.0587 or (.2 x .058) +(.05 x .942).