Anyone wanna take an open mind for a minute? Someone else brought up a good argument- water and building blocks for life are *everywhere*. Recent discoveries point to complex and potentially life-forming DNA-like molecules happening naturally on asteroids throughout the universe, which could easily seed life all over, and asteroid impacts seed life all the time anyway (er, maybe). So the question becomes- shouldn't we be looking wherever there's life on Earth? And there's life on Earth... pretty much everywhere. Under heavy pressure, under light pressure, in water and in methane and deep beneath the crust feeding on minerals. We actually have good reason to believe there's life out there in our own solar system, even if it's just microbes feeding on ice caps. Water is still our best indicator, sure, but it would suck incredibly much for us to miss out on a wealth of planets covered in swarms of life (even non-sentient life) just because we didn't use indicators we already know about.