Cosmology and Our View of the World

March 8, 1999


The Anthropic Principle

led by Howard Murphy


Mr. Murphy began by passing around a handout he had compiled explaining the tenets of the Anthropic Principle. He then gave a brief lecture on the historical foundations from which the Anthropic Principle sprung. Aristotle and Ptolemy asserted that the earth lay at the center of the solar system and universe. Aristarchus and Copernicus argued that instead the solar system was heliocentric. This theory evolved into what became known as the Copernican model, with the sun at the center and the planets orbiting around that sun. Scientific theories of the universe have gone on to show us that not only does earth not occupy a central role in the solar system, but that our solar system is just one of many in a galaxy, and that our galaxy is nothing rare in the entirety of the universe. The Copernican system began a trend in which human existence takes on an increasingly unimportant role. The Anthropic Principle was created to oppose the Copernican trend and bring man back to the forefront. It is an attempt to re-impose philosophy, such as that pursued by Aristotle, on science.

Mr. Murphy stated that in order for us to understand the cosmos, we must take into account the fact that we are here to ask what the universe is about, that without rational life, there could be no universe because there would be no one to understand it (this relates somewhat to the paradox, if a tree falls in the forest where no one can hear it, does it make a sound?). Professor Möbius then interjected that he felt this interpretation went a bit too far.

Mr. Murphy explained that there are two main branches of the Anthropic Principle, the strong and the weak, plus a lesser branch, the Theistic Anthropic Principle. The Strong Anthropic Principle (SAP) strictly constrains any universe to one that is constructed so that it produces sentient beings, that is, beings, who can observe its workings. The Weak Anthropic Principle (WAP) is less constricting in that it only insists that THIS universe was necessarily constructed in such a way that sentient beings would come into existence to observe it. The Theistic Theory states that the conditions of our universe, which allowed humanity to exist, were created on purpose. In this way, the Anthropic Principle shows a place for God.

The weakness of the theory, which was immediately pointed out, is that we cannot test these postulates because if other universes do in fact exist, we still have no access to them.

The Anthropic Principle, particularly the SAP, seems to discourage alternate universes, because it shows that if one law of the universe, such as gravity, was altered even minutely, our universe as we know it would become impossible. Mr. Murphy suggested that the SAP led to the possibility of only one universe, but Professor Möbius felt this was an exaggerated outcome. 'Why could a universe not develop with laws entirely alien to anything we human can fathom and still end up with some manner of sentient life?' was a point raised by one student. Several in the group argued back that no life was possible without the conditions we are familiar with. It was then questioned whether a "universe" that does not have the same fundamental forces as ours can even be called a universe? Such a universe would be both unobservable and inconceivable. Both Mr. Murphy and Professor Möbius argued that a universe that is inconceivable is the same as one that does not exist. There is no point to arguing over a possibility we have no way of understanding. This controversial point was taken up by the group for some time.

The APs lean toward a Theory of Everything (TOE) through which all the principles of the universe are connected and compiled. The discovery of a TOE would support the theories of the Anthropic Principle, by proving that either this universe is the ONE universe, or all other universes are exactly the same as this one. "Thats physicalism," stated Mr. Murphy. "No! That's fatalism!" countered Professor Brockelman. He continued that he was uncomfortable with putting humans at the center again. It is too anthropomorphic a theory to put faith in, and it constricts free will.

The lure of the Anthropic Principle is that it gives humanity the preference that science seems to keep stealing away. Rather than just a fluke of elements that will vanish before long, leaving no measurable trace on the universal order, mankind becomes the point again. It makes our lives more special. It is also comforting as an organizing period because it shows that there is a working order and rationality to the universe, a rationality, which many have interpreted as God. Instead of closing off God's options as so many other scientific theories, as all other sciences have done, it opens up a window for Him. It also shows the interconnectedness of everything in existence. Even if one little aspect of our universe were shifted, life as we know it would be no more than a myth.


Summary written by Allison Smith