Biologist Richard Dawkins makes a case for "thinking the improbable" by looking at how our human frame of reference — the things we can perceive with our five senses, and understand with our eight-pound brain — limits our understanding of the universe. Think of it: We can't see atoms, we can't see infrared light, we can't hear ultrasonic frequencies, but we know without a doubt that they exist. What else is out there that we can't yet perceive — what dimensions of space, what aspects of time, what forms of life?
"Science, Delusion and the Appetite for Wonder"