fun with the Drake equationA tad simplified, but it generally gets the point across. It boils down to the question of why you think there is life on earth.
If you believe life developed through scientific processes, the question of life existing elsewhere is more a matter of how common it is rather than if.
If you take a religious view of creation, it depends on whether or not you think God created life in more than one place.
Whether or not life from elsewhere has stopped by to visit is a totally different question. Therin lies the
Fermi paradox
Poll
