Many people scoff at individuals that believe in the existence of aliens. Often, while these critics roll their eyes at the possibility of “little green men,” they do believe in a “god.” The intention of this post is not to challenge anyone’s religious beliefs; nor is it to defend “alien abductees” or “ancient astronaut theorists,” but rather to explore the basis of these two beliefs.
It must be conceded, I think, that both beliefs (i.e., existence of god(s) and of aliens) requires what William James called a leap of faith as there really is no empirical evidence of the existence of either. Even if one concedes the existence of a historical Jesus, for example, (which is still not confirmed outside the realm of belief), there is no scientific evidence to support his divinity. The Bible or any other sacred text cannot establish the existence of a god because use of such “evidence” is simply “begging the question” or engaging in circular reasoning (e.g., god exists because the sacred texts says so and the sacred text is correct because it was written or inspired by god”). And while there are videos out there that claim to show UFOs, more often than not, there is a terrestrial explanation for the UFO phenomenon; where there is not, no definitive conclusions can be reached.
I think the alien advocates do have one advantage over the religious believers: statistics and probability. Perhaps the most famous formulation is the Drake Equation. The SETI Institute explains the Drake Equation:
The equation is usually written:
N = R* • fp • ne • fl • fi • fc • L
N = The number of civilizations in The Milky Way Galaxy whose electromagnetic emissions are detectable.
R* =The rate of formation of stars suitable for the development of intelligent life.
fp = The fraction of those stars with planetary systems.
ne = The number of planets, per solar system, with an environment suitable for life.
fl = The fraction of suitable planets on which life actually appears.
fi = The fraction of life bearing planets on which intelligent life emerges.
fc = The fraction of civilizations that develop a technology that releases detectable signs of their existence into space.
L = The length of time such civilizations release detectable signals into space.
The universe is vast. In 1999, the Hubble Space Telescope estimated that there are at least 125 billion galaxies. See http://imagine.gsfc.nasa.gov/docs/ask_astro/answers/021127a.html A drawf galaxy can have as “few” as 10,000,000 (ten million) while the largest galaxy discovered has 100,000,000,000,000 stars (that’s one hundred trillion). Our home galaxy, the Milky Way, has 200,000,000,000 (two hundred billion) stars. The Andromeda Galaxy, our neighbor, contains around a 1,000,000,000,000 (one trillion) stars. It’s estimated that our galaxy contains about 4.6 billion planets alone. See http://www.universetoday.com/30296/planets-in-the-galaxy/ You don’t need to be a math prodigy to get the point.
In simpler terms, the universe is just too vast (and getting even more so) for us to be the only intelligent life that has ever existed. And to my religious friends, I simply say–an omniscient, omnipotent god would certainly not create a vast universe and waste so much space…