Many people do not believe inUFO or ET. There is a strong camp for this disbelief.
It is similar to the argument in religion as whether or not god exists.I think many people will only believe what they see with their own eyes, and god and aliens are not visable to the eyes.We are designed to process data accurately i.e what we see with our own eyes.I think otherwise many people would not be able to distinguish this phenomena from some type of Spirit world going on.An unsound belief system.
Aliens are not "Out There".They are "In There".Within.
inner space is sa fith dimension.Aliens are high inteligences that have grown or evolved into more dimensions that we are familiar with.We live in the 3 dimensions of space and 1 of time , making a 4 dimensional experience or understanding of reality
There are many special dimensions not just 3 or 4.So you have to think outside the box to understand aliens.The material world is contained in the 4 dimensions we know, but other special dimensions exist ,say 5,6 ,7 or 8 dimensions.Where aliens exist.So as you continue to think outside the box from one dimension into a higher one, so that becomes the nature of reality.Our reality os confined to 4 dimensions and the normal mind will not accept a differrant reality to that.So , with this view aliens or god do not exist.
If you were living in a 3 dimensional world, you would not want to go and live in a 2 dimensional world, and so in , in 4 dimensional world, you wouldn't want to live in a 3 dimensional world.So on to 5,,6,7,,8 dinmensions etc, want to live in a lower dimension,So aliens who have grown further than our 4 dimensional world would not want to live in the solid dimension for too long.
So as far as we are concerned it can be said to be true that there is no such thing as ET in our universe.In our experience or reality.
So it is a truth to be athieston the subject as well as a believer,Either could be true according to your religious belief, so to speak.