Judea Pearl

Judea Pearl (born 1936 in Tel Aviv) is a UCLA professor whose Bayesian networks gave machines a principled way to reason under uncertainty — work honored with the 2011 Turing Award. He then spent decades building the mathematics of causality, the do-calculus and the “ladder of causation,” culminating in the bestselling “The Book of Why” (2018). He is also the father of murdered Wall Street Journal reporter Daniel Pearl, in whose memory he co-founded a foundation for cross-cultural understanding.

Curve fitting versus cause and effect

Pearl greeted the deep-learning revolution his own probabilistic work helped enable with conspicuous impatience. In a 2018 Quanta interview he said the field’s impressive achievements amount to “just curve fitting” — sophisticated pattern-matching that cannot ask what would happen if the world were different. “Associations are not enough — and this is a mathematical fact, not opinion,” he argued: without causal models, machines cannot reason about interventions or counterfactuals, the things that make intelligence useful.

The critique is a builder’s, not a doubter’s. Pearl believes strong, human-level AI is achievable and desirable — machines equipped with models of reality that could serve as moral reasoners, and that will, he says flatly, have free will, detectable when robots start telling each other “you should have done better.” His complaint with the deep-learning era is that it stopped one rung up his ladder, mistaking prediction for understanding.