I am talking about informational entropy, but using the analogy to pressure as a intuition pump. This applies whether we are using neutral nets or other PGMs. In fact, I was thinking of causal BNs as ideal approximations of human rationality, and noting the additional fact that there seems to be some cost to maintaining uncertainty that seems to fit the earlier analogy. (Sorry if I'm unclear - I will reread and try to clarify when I'm not on my phone.)