Actual Causation and the Art of Modeling

[Introduction] In The Graduate, Benjamin Braddock (Dustin Hoffman) is told that the future can be summed up in one word: "Plastics". One of us (Halpern) recalls that in roughly 1990, Judea Pearl told him that the future was in causality. Pearl's own research was largely focused on causality in the years after that; his seminal contributions are widely known. We were among the many influenced by his work. We discuss one aspect of it, actual causation, in this article, although a number of our comments apply to causal modeling more generally.