trying to snap people out of it for twenty years without success so far okay so this is the what I just showed you is the conditional version and there's an unconditional version where you don't actually have an observation the only thing you want to know is like model the internal consistency of why and really those two problems are not that different from each other in the first case you know a priori which set of variables are observable in the second case you don't know which part of why it's going to be observed and so here