Many of us may think the universe is teeming with life but that doesn’t make it so. A lot of the discussion about exobiology is driven by people who “want’ there to be abundant alien life, but we know almost nothing about the processes between a prebiotic environment and even the simplest life forms. How many independent steps are needed, what is the probability of each step occuring, what is the probability of each step occuring in the right order, and so on. The origin of life may be an almost inevitable transition, or it may be very difficult and therefore extremely rare. We just don’t know; and our uncertainty should be the starting point for a rational discussion of exobiology. Yes, we absolutely should be figuring out ways to detect planets with life, but until we have evidence to the contrary we should be prepared for them to be few and far between.