Encyclopedia of Opinion
Question
Do aliens exist?
Position2 of 4
No, alien life doesn't exist elsewhere in the Universe
Argument2 of 2

No alien life will ever exist in the universe

Not only does life currently not exist elsewhere in the Universe, it has never existed and will likely never exist in the obervable universe

The argument

All arguments that apply to the idea of no simple life forming outside of earth apply to this, amongst other cases detailed below: 1) The Fermi Paradox: This is a logical argument that is often used to support the idea that intelligent civilisations are likely extremely rare in the universe. The paradox goes as follows: There are over 100 trillion stars in the known universe, many of which are older than our Sun, and around at least some of these stars there will be planets that are Earthlike, and hence have a probability of developing an intelligent civilisation. And of these, a fraction will develop interstellar travel. Using simple modelling it has been shown, even for a relatively slow interstellar civilisation, the MilkyWay could be conquered on the scale of tens of millions of years. A tiny fraction of how long the Universe has existed for. From Earth, we see absolutely no evidence of any interstellar civilisations, such as Dyson swarms or any form of communication between stars in any of the millions of galaxies we've observed. The fact we see none is a strong case against the existence of intelligent life. 2) The Drake Equation Similarly to how the Drake Equation(See argument for there being intelligent life in the Universe) can be used to argue for the universality of intelligent life, it can just as easily do the opposite due to its highly speculative nature. Using far more conservative numbers for the calculation we obtain a value for the number of intelligent civilisations in our Universe as being 9.1E-11 or 0.000000000091 per Universe. So if we are already here, the chance of there being another is closer to 9.1E-22( 9.1 with 22 zeros' beforehand).

Premises

[P1]By the Fermi Paradox, if intelligent civilizations were common, even a slow one could colonize the Milky Way in tens of millions of years, a tiny fraction of the universe's age. [P2] Yet from Earth we see no evidence of any interstellar civilizations, no Dyson swarms or signals across the millions of galaxies we observe. [P3] Conservative inputs to the Drake Equation yield a vanishingly small probability of even one other intelligent civilization existing. [C] Therefore, because intelligent life is so improbable and undetected, alien life doesn't exist elsewhere in the Universe.

Counter-arguments

Counter to the Fermi Paradox: The most commonly used solution to the Fermi Paradox is termed the "Rare Earth" hypothesis which disputes the idea that Solar Systems that contain Earth-like planets and conditions are common. It instead proposes that there is something special about either our location in the quiet galactic arm or possibly something else such as specific concentrations of certain chemicals and molecules that has allowed Earth to form simply making life rarer than we expected, but not non-existent Counter to the Drake Equation: Almost all of the terms within the Drake Equation are either rapidly evolving or simply unknown values that lots of groups speculate to be different values. Using the figures that you estimate to be correct you can obtain almost any value within the Drake Equation to fit your agenda

Rejecting the premises

Like much in this topic, the assumption that there have been billions of chances for intelligent life to arise is purely speculation. The rare earth hypothesis states that there may, in fact, be something special/rare about our location in the Universe that we don't yet know about that has allowed life to evolve. The Drake Equation can be used to give essentially any value you want depending on what you estimate the input values to be as almost all of them are at best, very rough estimations.