rotatingpaguro

Judea Pearl is a famous researcher, known for Bayesian networks (the standard way of representing Bayesian models), and his statistical formalization of causality. Although he has always been recommended reading here, he's less of a staple compared to, say, Jaynes. So the need to re-introduce him. My purpose here is to highlight a soothing, unexpected show of rationality on his part. One year ago I reviewed his last book, The Book of Why, in a failed[1] submission to the ACX book review contest. There I spend a lot of time around what appears to me as a total paradox in a central message of the book, dear to Pearl: that you can't just use statistics and probabilities to understand causal relationships; you need a causal model, a fundamentally different beast. Yet, at the same time, Pearl shows how to implement a causal model in terms of a standard statistical model. Before giving me the time to properly raise all my eyebrows, he then sweepingly connects this insight to Everything Everywhere. In particular, he thinks that machine learning is "stuck on rung one", his own idiomatic expression to say that machine learning algorithms, only combing for correlations in the training data, are stuck at statistics-level reasoning, while causal reasoning resides at higher "rungs" on the "ladder of causation", which can't be reached unless you deliberately employ causal techniques. My rejoinder to this is that, analogously to how a causal model can be re-implemented as a more complex non-causal model[2], a learning algorithm that looks at data that in some ways is saying something about causality, be it because the data contains information-decision-action-outcome units generated by agents, because the learning thing can execute actions itself and reflectively process the information of having done such actions, or because the data contains an abstract description of causality, can surely learn causality. A powerful enough learner ought to be able to cross such levels of quo