Watch out for the human
What are aliens? This is a very interesting question, although an answer can only be given to the question: what do humans think aliens are? Answer: Deformed creatures from a planet light years away that come here in an attempt to take over our world. That's what many people would say, especially when they've seen a good number of science fiction movies.
But another interesting question is: what would aliens think humans are? Answer: “Deformed creatures from a planet light years away that come here in an attempt to take over our world”? Exactly. A completely neutral observer – a god of the universe – would see no difference between the inhabitants from Earth and those from other planets. Yet, if he had to, how could he describe humans from earth to, for instance, a Martian?
This universal god could say that humans in general are a quite arrogant people as they assume he – God – made the Earth, and all it contains, for the humans to use and benefit from. He tried to tell them in various ways – wars, illness and natural disasters – that it was never his intention for them to be superior, but his warnings never seem to get through to them.
He could say that humans are rather ingenious as they utilise Earth's resources to make modern equipment to make life easier and to discover ways of exploiting planet Earth, and eventually maybe even the entire universe, to the teeth.
He could say that humans are fairly selfish as they would do anything to creatures that are 'different' if it were to be beneficial to them in any sort of way. This has been seen time and time again, in the past as well as in present times, in their treatment of nature, in their care of slaughter-animals and even in their associations with other humans.
With all this arrogance, ingenuity and selfishness, he could say, humans could eventually, one day, if they survive despite ignoring his warnings, be able to take over other planets and gain absolute power...