Why do people say there is no evidence of aliens ?

Saying there is no evidence of aliens does not imply that they don't exist. We just don't have any proof of their existence. 
There is lots of evidence for black holes. We see effects of their gravity. We see stars orbit around them. We also see the effects of dark matters gravity on the rotation rate of galaxies. That is where the idea of dark matter came from. 

Because there is simply no evidence. Doesn't mean they don't exist, Just no evidence.

And how does any of that translate to evidence of aliens?

Absence of Evidence is not Evidence of Absence

Explaining why there's no evidence doesn't mean there's evidence..

Because there is no evidence.  I'm not sure what's unclear.

.....because there’s no evidence of aliens?

Probably because there is no evidence of aliens.


Duh.

Because there isn't any.

If there are inhabitable planets, even at lightspeed it would take at least 4 years to get from there to here.

Accelerating to lightspeed and back at a rate that life can survive would take ages, not to mention infinite amounts of energy

I think you answered your own question....

"Why do people say there is no evidence of aliens ?"

Because: 
We don't have the means to explore the outskirts of space deeply. 

So far, there's been no official evidence of alien presence here on Earth, and until we're able to explore other planets, we don't have a means of inspecting them for life... 
So, the conclusion is, although ET intelligence may exist - we don't have any evidence for it.

You're confusing our extremely meager ability to detect aliens with claims of no evidence for their existence.  People say there is no evidence for aliens because so far there is no evidence for their existence.  Astronomers keep looking for evidence for the very reason that so far they haven't found any evidence.

People say there is no evidence of aliens because there is no evidence of aliens.

The universe is huge. It is so big its size is simply outside of our everyday experience and we cannot truly grasp its size. However, that alone is not evidence aliens exist. It just makes it seem improbable ours is the only planet with life on it.

We do know there any many other planets in the universe. However, again not evidence just suggestive some may have life on them.

You claim there are so many planets similar to Earth. I would like to have had some source for that claim cited. I am aware of many other planets but am not aware any are like Earth or even possibly have the consitions in which life could exist.

What we do not know is the probability of life starting even where the conditions would be favourable to life. If the fact is that probability is very low it is possible Earth is the only planet with life on it.

Alternatively, if life is almost inevitable under the right conditions then we would expect life on any planet with the right conditions. What we do not know is if the Earth is the only planet with those conditions or if there are a lot of them.

Because our universe is so massive it could be that if some other planets have life on them they could be spaced so far apart from each other that life on any of those planets cannot detect life on any of the others.

There certainly may be other planets in the universe with life on them. However, we have not detected life any any other planet. Therefore, we do not have any evidence of extraterrestrial life. This makes the statement there is no evidence of aliends correct.

There is no definitive empirical evidence of aliens.  There is only evidence of UFOs which could just as easily not be aliens. Until such time that evidence is provided that aliens themselves exist, I reject any claim that they do. 

Because there is absolutely no evidence of extra terrestrial aliens on Earth now and no undisputed evidence that any ever were here.  While it is extremely likely that the galaxy (and universe) is densely populated, there is currently no evidence to prove it.  Saying that there are no aliens is different than saying that there is no evidence that aliens have ever visited Earth.

We KNOW there are Aliens out there, for the reasons you mention AND for the same reasons we KNEW other Planets went around other stars, before we discovered the first one.------What we know about the universe strongly suggests so.

But they are right, there is NO evidence of specific Aliens.  Sure UFOs exist, but there is no evidence that they are "Alien Spaceships"  We don't know WHAT they are.  And CONSISTENT reports of "Aliens" and "Abductions" that describe the same sort of being, even if true, is not evidence of "Aliens" either.------They could be native to Earth (or underground) as far as we know.  There are seen HERE, on the ground, not in space.

For exactly that reason:  they COULD harbor intelligent life, but we don't know for a fact they do, and they are generally so far away, that we are seeing snapshots of plats from thousands of years ago.

There's a real definite chance that life as we know it exists on other planets, yes.
But that is not the same thing as evidence.
Evidence means we can prove it.
Life on other worlds? We can't prove it. We suspect it, but we cannot prove it. We are looking for evidence.

Because that is a true statement.  There is no Actual Evidence.  Sure there are plenty of Planets out there in the Universe that could support life.  But we don't have any Evidence (yet).

Black holes have been detected.  There are alternatives to dark matter such as modified Newtonian dynamics.  There is little or no evidence for the existence of extraterrestrial intelligence for the reason you mention in your first sentence.  That doesn't mean there couldn't be, but at its best science operates on what can be firmly established and is agnostic about the rest.

They say there is no evidence that we can see at this time, no proof that we can examine to prove aliens exist.

There is no confirmed evidence for the existence of alien life.  There are reports of things which suggest that aliens have come here and visited (and are still visiting), but people tend to question how reliable the witnesses are or were.

As to other planets, we haven't seen anything to indicate that there must be life on them.  The odds seem pretty good that there ought to be, but ought to be and actually seeing it are two separate things.  The second would involve evidence.  The first is not considered evidence.  It is an indication, a clue, but not evidence of anything.  We actually have seen real behavior consistent with the existence of black holes and dark matter.  In fact, we know of "dark" matter from evidence, but we don't know what the evidence really indicates.  It might not actually be "matter".  There is something though.

I don't think you understand the meaning of evidence.  Conjecture is not evidence, but prediction of phenomena which is later observed is evidence.  Right now, we are at the conjecture stage when it comes to life on other planets.  We haven't seen the things we predict we ought to see if there is life (as we know it).

Saying there isn't evidence is different from saying they don't exist. Evidence hasn't been found yet, but maybe there will one day. I personally think given how large the universe is, there probably are aliens. I think we'll either find them or humankind won't be around long enough to find them.

Intelligent populations on other planets? I am not sure we have an intelligent population on this planet.

If other planets populations had the intelligence to reach our planet why would they want to be here? We are in the process of destroying earth. If they wanted it they would simply destroy us and let it regenerate itself and then take it over.

Saying there is no evidence of aliens is not quite the same as saying there are no aliens.  Unlike discussions about religion, where logic can disprove certain issues, there is no logic available and no evidence available to prove or disprove existence for ET-type aliens.

There is plenty of evidence that people say they see aliens. Books have been written, movies made, and jokes told about them. Therefore aliens are a real phenomenon. 

However this evidence is all based on testimony, dubious interpretation, story telling, and outright fakery. No physical evidence exists. Since there is no physical evidence, space aliens are not a subject for the physical sciences. However they are a rich field for research by psychologists, sociologists, and pub philosophers.

There are close parallels between the phenomenon of meteorites and space boogiemen. Meteorites were ignored by physical scientists and the whole subject was treated as a myth:"stones can't fall from the sky because there are no stones in the sky". This all changed when a "Stone" was seen to fall from the sky, the stone was recovered and then examined by a real scientist, who declared that the physical properties of the "stone" could not possibly have formed on Earth. Meteorites have since become a serious and valuable tool for astronomers.

With space aliens, the evidence keeps piling up that a real phenomenon is at work in our present day culture. However the evidence is not physical evidence. It only proves that people want to believe in boogiemen up in the sky.

The day has never dawned when an alien ashtray, cigarette butt, square of toilet paper, or toothbrush has been presented to a qualified scientist to analyze in a professional laboratory then publish the results in a respectable journal and survive peer review. If such evidence ever comes to light, then we can conclude that space aliens exist. I suggest it would be wise to prepare oneself for the certainty that this will never happen.

We are alone. Celebrate the fact. And enjoy the tall stories.

Perhaps we need to get our own house in order first.

Is it perhaps because that is the truth? Do not take me wrong. There are many unexplained, mysterious and supernatural  things out there but life on an other planet is not one of them. Why do we not clean our own house first and put our priorities right. Why would we want to spend billions looking for something that does not exist when many people on our very earth are hurting and going to bed hungry. i am convinced that you will get the answer to your question by setting the priorities right in your life!

To believe that the human race really could believe that they are unique seems unbelievable . It could be however that they would like to think so.  Look around, and you will soon find people who fall into this category.
For them to accept that they are inferior to an alien race would be impossible for them, hence their denial attitude.

Evidence; contact NASA, the Mars Society, Jeff Bezos(Blue Origin) org.  I'm sure there's a mountain of proof that we aren't the only life forms out here in this galaxy

we have detected black holes thru powerful telescops that measure the depth and intensity of light itself ... and different wavelengths of light can see different ways of the same object traveling thru space dark matter is something scientist think drives the expansion the universe itself away from the center  


do aliens exist... maybe not the et type ones people always think of ..

but any type of life on a earth like planet that is not a bunch of african apes could be labeled as life on other plants from the micro size to the macro size .. im not not gonna say aliens dont exist

but i will say that if there was intelligent life and saw us they probably turned around and left not even noticing what we are or what we are doing the same way you pass by an earth worm ,,....


life is random ... its like rolling dice yopu dont know what your going to get if life does exist even alien life it has to go thru  a whole tidal wave of chaos and survive thru it to walk the planet as a species and become discovered


i agree with what richard dawking said

there is probably  a whole lot of life in the universe its just the universe is sooo vast that the island of life are so far apart that there is little to no chance for one form of life to witness another ever

Because usually the military and governments clean up and contaminate the sites before neutral parties can examine the site and gather evidence. Only 2% of UFO sightings remain unexplained. The Navy mainly emitted UFOS are real in late 2019.

Terrestrial aliens?are definitely real.  

insecurity................................

Aliens, in general, on other worlds? Certainly, it would almost be statistically impossible for them to NOT exist somewhere in the universe. Aliens advanced enough to come here?

Interstellar travel is SUCH an ENORMOUSLY difficult undertaking that automatically and by definition, any alien race capable of it is so advanced, that we could do nothing against them if they were hostile, and if they were interested in observation and/or blending in,,,,, they would be so good at it, that it would never seriously occur to us that they were visiting us. They'd be mind-bogglingly good at covering their tracks, better than any Area 51/X-Files (MIB, SciFi comedy etc...) would have us believe. Therefore, I don't know what UFO sighters/abductees are seeing, but I know what they are NOT seeing, namely, Aliens. So, no, I (and most other scientifically literate people) don't believe in aliens having visited Earth.

Of couse there is evidence. Just look at Trump

What they mean is, WE have no evidence of aliens. And since we can't explore beyond our own system, it is also true that we have no evidence of their absence either.

well honestly i never seem one in reality off the internet except in this extreme horror survival movie called extratersial 

No Physical evidence but the probability supports the possibility of alien life somewhere in our galaxy besides ourselves...

And how many Galaxies are there in the universe with only 2 life forms in them is still a lot however Life can be as small as a single celled organism what most think of is something along the lines of intelligent life and whether or not our own species qualifies is still up for grabs...

N.Shadows

There is a possibility of life on other planets, but there is no evidence. We have not received signals, or seen any aliens. That means no evidence. 

Certain people can’t see or envisage beyond their own existence. You’re right, we live in such a big Universe with so many other planets and galaxies, that we shouldn’t discount other races. I’d say it’s almost certain that there is life on other planets. 

The fact there is no evidence, does not mean they don't exist. There might be evidence lying around and we are just not aware of it’s existence. Same thing could be said about weather or not Gods exist. But I believe we’ll eventually find out as we explore space beyond our solar system.

I think aliems is real.

There was that one episode in 1940ish Roswell New Mexico, but I never saw any proof and who cares anyway. I do believe that life not different from ours exists on planets in different galaxies far, far away. But Hollywood has dome some really scary stuff about Alien invasions on earth. Try the remake of War Of The Worlds with Tom Cruise. Takes place in a borough of NYC. Really frightening and mood changing. Some of the best special effects ever done.

Trying to find and prove that there is life on another planet is the same effort as trying to find ghost in an old building.  

The point..... what for?  there are better things to do like trying to find a solution to stop the corona virus.   OR finding a more efficient way to replace liquid gas.   

I’d like to think we are not alone in the universe, but the physics of space travel make it hard to believe a being from a distant galaxy could get to Earth. But that’s not to say man won’t discover a way. Maybe with the advancement of AI someday we will at least send an explorer or some distant alien will send one to us. But presently it doesn’t seem plausible any time soon.

You mean ALF wasn't real?

Is there evidence?

We haven't seen black holes or dark matter.  We have seen evidence of both.  So we THINK they exist.  We can quote how many stars and planets there are.  So we can conclude that the probability of alien life exiting is probably high.  However, in 2021 there is no concrete evidence that alien life does exist.

Evidence is now the police might say there is no evidence of fowl play

Evidence is now the police might say there is no evidence of fowl play

What PROOF do you have of an alien .. if NONE  then there is NO EVIDENCE 

WHAT is the problem with english

just because you THINK  there might be one doesnt    MEAN ITS EVIDENCE

Evidence of aliens have been proven fact over the years there's been sightings of UFOs and many other things such as Roswell there's also been claims that people were abducted by aliens this is the only one I do not believe as aliens will not harm us they have been on Earth before our government even knows they exist

Apparently there IS evidence, here on earth.
Accountsof detailed abductions, confirmed sightings, people sworn to secrecy have spoken, measurable radioactive readings in areas where people have seen a UFO land, etc... NOT to even consider exactly what governments around the world "know" and do not share with the general public.

I believe there ARE Other forms of life in the universe other than men/women and children on Earth. 

Perhaps egos and pompous attitudes won't allow some to realize there is greater intelligence than human kind.

Kind of like the mindset of the people who believe all of the uncovered ancient civilizations found all around the world from mountain tops to under the ocean waters...who believe it was all carved with a hammer and a chisel.... giving no credit for superior intelligence that humans have yet to discover or figure out.

There is life out in the universe it just trying to find a way to communicate  with them,too many planets being found ,maybe they have contacted us in a way we cant understand

Take a trip with alice down the rabbit hole. See how deep it goes and you will find that there is evidence everywhere. :D


However, much like Alice you might stretch your dimensions of conscious a bit...


https://www.youtube.com/watch?v=SrJuy8cBKD8

I spoke to Eugene Cernan, the last man on the moon years ago and asked him that very question.  What he said was given the millions and millions of stars and planets in the heavens the situation is obvious.  the problem is at our present level of development man may not be able to comprehend the obvious or the evidence that it exists.  i agree and feel the millions of people who vote idiot left in our nation at every turn are proof of that.

whats a black hole got to do with aliens anyway . 2 different issues .. good try troll ..

Plenty of evidence, and lots of cover-up. It is ignorant and conceited to think we are the only intelligent life in a universe that is infinite.

Look at the size of the universe. Were basically a speck of dust compared to the rest of the universe. It doesn't make any sense to me to be so stubborn that people chose to believe that there isn't aliens because we have no evidence. What type of evidence do they require? The population of the planet has known for hundreds that the earth isn't the center of the solar system. We exist, so why couldn't there be a advanced civilization that is so advanced to were they've be able to make it too our planet? The reason they don't come out and reveal themselves is because of the culture shock it would cause to the people of this planet. We'd be forced to question our beliefs, beliefs that civilizations have had for thousands of years. I chose to believe they do exist, and with the reasons I just typed, I also believe that their not able to interfere in our evolution as the people of this planet. Maybe we have to get to a certain spiritual and technological advancement before they can reveal themselves. Id hate to think that mankind out of the massive mind blogging size of the universe is the only species that exists. We need to stop being so stubborn and believe!


P.S would you really want to come right out and "We Exist!" with the warlike nature of our species?

Because then they would have to 'deal' with it.