Javier DeFelipe writes eloquently about the progress from our basic understanding of two neurons to efforts to map all neural connections in a recent commentary. Check it out. At one point, he writes that “circuit diagrams of the nervous system can be considered at different levels, although they are surely impossible to complete at the synaptic level.” However, he doesn’t offer a time scale for this prediction. I agree with him that it would be impossible given our current technology, but at some point in the future, who can say? One thing we know is this: past bets against advancements in science have not fared well.