Is it stupid to doubt the existence of extraterrestrial life?

Question

Certain facts about space are widely accepted:

1) It is REALLY big... many claim infinite. This means there are near infinite chances for the right life supporting conditions to occur on at least one other planet.
2) That humankind could neither visit nor observe 99.9999% of it even if we could travel at light speed. As such if life already existed we probably wouldn't know about it.
3) That scattered throughout space there are millions of solar systems like ours. Each planet with its unique climatic characteristics.
4) Space based life forms (even earth based ones) do not have to be carbon based. Silicon or Sulphur would work too.
5) Finally the majority of the world's population claims to believe in some god. If people believe in a larger creator how would life on other planets seem so impossible?

There are some excellent answers here... To the scientific approach folks I respect the "need for proof" you are conveying.... but if you had to guess one way or the other for the record which way would you go?

Answer 1

All of your facts seem correct. Although I tend to agree with dendronbat on 4.

It would be wise to believe in the possibility of extraterrestrial life. It would be foolish to state that because of this possibility, such life does in fact exist. One should not take the corollary that something could exist therefore it does exist. This would be stupid.

We can approach this subject in many ways. The best is a scientific one where we leave our opinions behind.

Regarding your points 1, 3, 4, and the fact that the chemicals throughout the Universe are roughly uniform, we arrive at the possibility of life forming throughout the Universe at a very high probability. Assuming that we keep in mind that, like our own Solar System, the high majority of planets that do form are not capable of sustaining life. In fact, it is the size and closeness of Jupiter that has determined how much water formed on the planet Earth. So there are many variables involved for life to be possible on a planet.

Concluding that extraterrestrial life is probable does not mean that we should accept it as fact.

Regarding your point 2, we must base our intelligence on proof. As of November 2007, there exists no proof. There does exist what is called paranormal evidence. This would be stories by others that would need to be accepted on a belief basis only. The same level as ghosts and bigfoot etc. One could base their belief upon these stories or photographs or one's own experience of seeing something strange in the sky. But this belief would not constitute proof.

To doubt the existence of extraterrestrials when there exists no proof of such is not stupid. It is only the scientific approach where one would need evidence to support a theory or conjecture. This is the only true way for us to advance in our knowledge.

It is not wrong to believe or disbelieve in extraterrestrial life. It would be wrong to state that such does exist without having evidence.

Answer 2

It would be stupid to 'believe' either extreme (extraterrestrial life must exist or it cannot exist).
The proper scientific approach is to doubt both 'absolute certainties' as long as proof does not exist.

1) If we could prove that the probability of life is not zero (or so close to zero that we can't tell the number from zero) AND if we could prove that the univers really is infinite, THEN we could have a high degree of certainty that there must be life somewhere else. But we do not have both proofs yet. In an infinite universe, the probability could be infinitesimal (number so close to zero...) an we could still exist as 'the accident'.

2) The fact that we cannot observe something does not mean that it exists... It simply amplifies the point that we have no proof of non-existence.

3) We do not really know what 'solar systems like ours' really means when it comes to calculating the probability of life's existence. The only solar systems that we have discovered so far as very unlike ours (most have big Jupiter-like planets close to their sun; our Solar system does not have that).

4) The fact that life could function differently helps build up the probability numbers. But we have never seen these other types of life, so no proof yet.

5) The God argument was already used -- twice, differently -- to 'prove' that extraterrestrial life could NOT exist (Thomas Paine and William Whewell). I never found the 'proofs' very convincing.

Answer 3

Life will find a way. For many years now, scientists have been finding life in places that were thought impossible. The organisms thriving on the black smokers at the ocean floor. Until a couple years ago, all life, flora and fauna were thought to be carbon based, until the discovery of silicon based life forms gaining sustenance on rock deep under the earths surface. To assume that we live on the only inhabited planet in the universe is ignorance at it's best. Who's to say that the universe itself is not a living, breathing organism? That would explain the faster than light communication seen in sub atomic particles. We don't know everything. We don't even know 1% of everything. There is life out there that we don't even understand as life, all we can do is try to learn.

Answer 4

I'm not sure about your statement that astrobiologists and astrophysicists believe that extra-terrestrial life is less diverse than those life-forms on Earth. Certainly they'd expect life-forms on other worlds to differ radically from those on Earth according to the conditions there - for example, if there was high gravity, methane-based atmosphere or low temperatures. Although microbes have been found on Mars, I'm not aware of samples from any other worlds, even within our own Solar System, so it may be that their hypothesis is based on limited evidence. As for how the appearance of ETs would affect Christiandom, I suppose it would depend on how logical the Christians were going to be. Classing them as demons and kicking off a Crusade might not be the best idea. Absurdism and Nihilism relate to finding meaning in life and/or in the universe. Humanity will have to take a giant reality check if ETs do appear - and the Absurdists and Nihilists will have to do the same. Obviously, the nature of the ETs will be a factor: pacifist Ewoks are clearly preferable to laser-wielding cyborg brain-eaters.

Answer 5

responding point by point:
1&3. Yes, there are many galaxies with many stars. The estimated number of stars in our universe has been estimated to exceed the number of grains of sand in all of the Earth. And planets orbiting stars seems to be a common phenomenon.

2. We may be able to at least detect the presence of life if it exists in planets around nearby stars through chemical signatures (David Charbonneau's work, for instance).

4. Sulfur does not bond with other elements in a sufficiently complex way to support the creation of complex macromolecules, and while silicon can do this, the nature of its bonds are too rigid to form anything alive. Chemically speaking, we seem to be stuck with carbon based life forms as the only possibility. Fortunately, our universe is filled with carbon as stars typically generate lots of this element by fusing 3 helium atoms together.

5. Can't speak for theological implications, but the scientific method has revealed that the chemical precursors of life are easily formed by natural chemical reactions. Therefore, any world that has water and basic elements such as C, H, O, N, P, S (which are all common throughout the universe) has probably evolved life. An entire new field, astrobiology, has recently emerged, based on encouraging research in the field of abiogenesis. You would probably enjoy reading the Journal of Astrobiology.

In a final comment, as an evolutionary biologist who has studied the evolution of life on Earth, while life may easily arise from chemical reactions to shards of phenotypic RNA up to something as complex as single celled microscopic life forms, breaking the ecological dominance of single celled creatures, to allow more complex life forms to evolve also requires a planet where cataclysmic geological catastrophes take place that periodically cause mass extinctions.

Answer 6

It is not stupid at all. We have no proof, or even any evidence, that life exists anywhere off the Earth. But it seems likely that life does exist off Earth, because all the same chemicals we have on Earth also exist in space. So most people ASSUME that such life exists, but it is just an assumption at this time. It does not make you stupid to disagree with an assumption.

Answer 7

No. There is not the doubt...
Actually, see the what condition is...
People who dont know what astronomy is have much more thinking for the existance of UFOs.
An expert in astronomy knows what really universe is and the possibility of life existance in he thinks decreases but not really closes.
This is why, astronomers try to keep away from dangerous questions and talk like this.

Actually, aliens can exist.
Many planets around different stars are found.

Answer 8

It's only stupid to doubt the existence of extraterrestrial life and then apply for a job as a reporter for the Weekly World News or some other tabloid ;)

(Seriously, I do not think it is stupid at all.)

Answer 9

what exactly is your point?

we all sit around watching "Star Wars" and "Star Trek" and getting indoctrinated with Hollywood's ideas about space written by people that still go 'WOW!' when they look at a telescope, if they ever even have.

Their opinion is that space is FULL of aliens, look close at any star and see them wave back at you... with at least 3 hands.

My point here is... that stuff is all fiction. The facts are that we have ZERO evidence of any extra-terrestrial life.

If life is out there - so what? We are unlikely to ever know one way or the other and back here on Earth I can't even get people to wear their seatbelts!

Focus, people!

Answer 10

No, I don't think it's stupid at all. Having heard the same theories you list, especially the vastness of the universe - and the majority of it unexplored by earthlings - I believe it's quite possible there's life beyond Earth.