Scientists once thought that whatever the initial conditions of the universe might have been, given enough time and a little luck, eventually intelligent life forms like ourselves would evolve. But instead, during the last fifty years or so, scientists have discovered to their surprise that the existence of intelligent life in this universe depends upon a complex and delicate balance of initial conditions given in the big bang itself. In fact, it appears that the universe has been incredibly fine-tuned for the existence of intelligent life from the very moment of its inception.
And this fine-tuning is beyond comprehension in its delicacy. To give you an idea of the delicacy of the fine-tuning, let me just give a couple of numbers to give you a feel for the odds. The number of seconds in the entire history of the universe, all the way back to the big bang, is about 1018, 1018 seconds in the entire history of the universe—ten followed by eighteen zeros—a huge number. The number of subatomic particles in the entire known universe is said to be around 1080.
Now with those numbers in mind, consider the following: In order for the universe to be life-permitting, the force of gravity and the weak force in the atom have to be fine-tuned to the precision of one part out of 10100. The cosmological constant that governs the accelerating expansion of the universe is fine-tuned to one part out of 10120. Here’s a real eye popper; Roger Penrose of Oxford University has estimated that the odds of the initial low entropy state of the early universe obtaining by chance alone, is one chance out of 10 to the power of 10123, a number which is so incomprehensible that to call it astronomical would be a wild understatement.
And the examples of fine-tuning are so diverse and so numerous that they are unlikely to disappear with any future advance of physics. The fine-tuning is here to stay and requires some sort of explanation of its existence. And in the literature on this subject, there are basically three possible explanations that are put forward. One would be physical necessity—that it’s due to the laws of nature; they have to have the values they do. Second would be it’s just pure chance alone. The third one would be it’s the product of intelligent design; someone has designed the universe to be life permitting.
The problem is that those first two alternative explanations, physical necessity and chance, are just not very plausible. There’s nothing about the laws of nature that require these constants and quantities to have the values they do. And the chances are so remote that they cannot be reasonably faced. So I think the most rational explanation is intelligent design. And a number of scientists have said this as well. For example, Paul Davies, a prominent physicist, has said, “Through my scientific work I have come to believe more and more strongly that the physical universe is put together within an ingenuity so astonishing that I cannot accept it merely as a brute fact.” And Robert Jastrow, who was the head of NASA’s Goddard Institute for Space Studies, has said that “This is the most powerful evidence for the existence of God ever to come out of science.”
So we can summarize the first argument as follows:
- if the universe began to exist, then the universe has a cause of its beginning;
- the universe began to exist;
- therefore the universe has a cause of its beginning.
We can summarize the second argument as follows:
- the fine-tuning of the universe is due to either physical necessity or chance or design;
- it is not due to physical necessity or chance;
- therefore, it is due to design.