What is "Earth-like"?

[mistermack]

Whatever the water situation is, the planet would be almost certainly easy for humans to live on, as it's surface gravity would be similar to our own.
Unless it's like Venus, with a runaway greenhouse effect. But the distances involved in getting to the NEAREST star make it understandable how we have never been visited by aliens.

...or they don't exist.

That would also be a reasonable explanation.

To be honest, it's a silly explanation.

So far, we only know of one planet, that has liquid water and light energy from a star.
And that one is full of life. So that's 100% positive for life evolving.

So even though it now looks like there are billions of similar planets just in the Milky Way, and Trillions and Trillions in the whole universe, why would it be reasonable to conclude that aliens don't exist?

That's about as logical, as believing that god made it all, just for us.

[rainbow]

Whatever the water situation is, the planet would be almost certainly easy for humans to live on, as it's surface gravity would be similar to our own.
Unless it's like Venus, with a runaway greenhouse effect. But the distances involved in getting to the NEAREST star make it understandable how we have never been visited by aliens.

...or they don't exist.

That would also be a reasonable explanation.

To be honest, it's a silly explanation.

So far, we only know of one planet, that has liquid water and light energy from a star.
And that one is full of life. So that's 100% positive for life evolving.

Extrapolating from a single sample is silly.

[Hermit]

Whatever the water situation is, the planet would be almost certainly easy for humans to live on, as it's surface gravity would be similar to our own.
Unless it's like Venus, with a runaway greenhouse effect. But the distances involved in getting to the NEAREST star make it understandable how we have never been visited by aliens.

...or they don't exist.

That would also be a reasonable explanation.

To be honest, it's a silly explanation.

So far, we only know of one planet, that has liquid water and light energy from a star.
And that one is full of life. So that's 100% positive for life evolving.

Extrapolating from a single sample is silly.

True. The single sample is all we have, though, and that is better than none at all.

[pErvinalia]

Give me an example of anything ever that occurs in the universe only once? This idea that we are the only lifeforms in the universe is religious bollocks of the highest order.

[JimC]

IMO it is extremely unlikely, but not altogether impossible (Dawkins discusses this well, and although, like me, he thinks multiple life origins highly likely, one cannot rule out that we are the result of a freak event)

[Sean Hayden]

A freak accident that occurs once every....in a universe this empty, from the right perspective everything's a freak accident, shirley.

[JimC]

Rationalia is the biggest freak accident of all!

[Brian Peacock]

Give me an example of anything ever that occurs in the universe only once?

The Universe.
Yo Mama.

[rainbow]

Extrapolating from a single sample is silly.

True. The single sample is all we have, though, and that is better than none at all.

Moot.

If there weren't a single example, we wouldn't be thinking about this at all.

[pErvinalia]

Give me an example of anything ever that occurs in the universe only once?

The Universe.
Yo Mama.

DaveDodo.

[Hermit]

Extrapolating from a single sample is silly.

True. The single sample is all we have, though, and that is better than none at all.

Moot.

If there weren't a single example, we wouldn't be thinking about this at all.

Of course we wouldn't be thinking about this at all. No surprises there, for we simply wouldn't be. That is moot.

Looking at the situation as it stands, at this stage we do know of only one planet capable of supporting life, and that planet does support life. It makes sense to speculate that there are gazillions of planets spread across billions of galaxies that contain around a billion stars each, that a few of them are capable of supporting life forms and that there is a real, though not calculable chance that extraterrestrial life does exist somewhere. It certainly makes more sense than saying something like: Even though planet earth supports life forms no other planet in the universe does.

[rainbow]

Extrapolating from a single sample is silly.

True. The single sample is all we have, though, and that is better than none at all.

Moot.

If there weren't a single example, we wouldn't be thinking about this at all.

Of course we wouldn't be thinking about this at all. No surprises there, for we simply wouldn't be. That is moot.

Looking at the situation as it stands, at this stage we do know of only one planet capable of supporting life, and that planet does support life. It makes sense to speculate that there are gazillions of planets spread across billions of galaxies that contain around a billion stars each, that a few of them are capable of supporting life forms and that there is a real, though not calculable chance that extraterrestrial life does exist somewhere. It certainly makes more sense than saying something like: Even though planet earth supports life forms no other planet in the universe does.

It also makes more sense than saying something like: Gribble wibble.

Since we have no idea as to how likely life is going to arise on some random planet, we can wildly speculate either way.

[pErvinalia]

It would have to be almost infinitely* unlikely, give the size of the universe, to think that this is the only place where there's life in the universe.

* - "almost infinitely"... that's like infinity minus one, innit.

[Forty Two]

Extrapolating from a single sample is silly.

True. The single sample is all we have, though, and that is better than none at all.

Moot.

If there weren't a single example, we wouldn't be thinking about this at all.

Of course we wouldn't be thinking about this at all. No surprises there, for we simply wouldn't be. That is moot.

Looking at the situation as it stands, at this stage we do know of only one planet capable of supporting life, and that planet does support life. It makes sense to speculate that there are gazillions of planets spread across billions of galaxies that contain around a billion stars each, that a few of them are capable of supporting life forms and that there is a real, though not calculable chance that extraterrestrial life does exist somewhere. It certainly makes more sense than saying something like: Even though planet earth supports life forms no other planet in the universe does.

Well, both of those statements make sense as possibilities. Neither of them make sense as a statement of knowledge because we just don't know.

It's possible Earth is the only one. It's possible there are billions. It's possible there are just a few. We don't know the likelihood of life forming.

It does make sense to speculate. Speculation is how we use our imaginations to divine possibilities to research and calculate. However, to say it makes more sense that there are billions of life-harboring worlds, as opposed to saying there is one life harboring world is incorrect. For one of those statements to make more sense, there would have to be some demonstrated assumptions known which are currently unknown.

I certainly agree that it is possible the universe is, relatively speaking, teaming with life. I also prefer to think of a universe filled with life than a universe of non-life and us. However, that preference is neither sense nor evidence.

[Hermit]

Extrapolating from a single sample is silly.

True. The single sample is all we have, though, and that is better than none at all.

Moot.

If there weren't a single example, we wouldn't be thinking about this at all.

Of course we wouldn't be thinking about this at all. No surprises there, for we simply wouldn't be. That is moot.

Looking at the situation as it stands, at this stage we do know of only one planet capable of supporting life, and that planet does support life. It makes sense to speculate that there are gazillions of planets spread across billions of galaxies that contain around a billion stars each, that a few of them are capable of supporting life forms and that there is a real, though not calculable chance that extraterrestrial life does exist somewhere. It certainly makes more sense than saying something like: Even though planet earth supports life forms no other planet in the universe does.

Well, both of those statements make sense as possibilities. Neither of them make sense as a statement of knowledge because we just don't know.

It's possible Earth is the only one. It's possible there are billions. It's possible there are just a few. We don't know the likelihood of life forming.

It does make sense to speculate. Speculation is how we use our imaginations to divine possibilities to research and calculate. However, to say it makes more sense that there are billions of life-harboring worlds, as opposed to saying there is one life harboring world is incorrect. For one of those statements to make more sense, there would have to be some demonstrated assumptions known which are currently unknown.

I certainly agree that it is possible the universe is, relatively speaking, teaming with life. I also prefer to think of a universe filled with life than a universe of non-life and us. However, that preference is neither sense nor evidence.

Billions? Teeming? I did mention that the chance of extraterrestrial life existing is not calculable. We just don't have enough data points to extrapolate from. Nevertheless, it is reasonable to say the chance is real because we do have one data point where the condition pertains. At this stage we have no data point of an earth-like planet that does not contain life forms.