On Causality and Causal Mechanisms: Comment on Dennis Lindley's “Seeing and Doing: the Concept of Causation”

Abstract

Dennis Lindley's review of Judea Pearl's book is a service to many (including myself) who have had trouble deciphering Pearl's mechanism. It is also a service to Pearl whose work will now be appreciated by probabilists and statisticians interested in foundational issues. My understanding of what is meant by causal mechanism is entirely due to Lindley's review, and based on this, my position is that Pearl's causal mechanism is embraced within the framework of Thus to me, the calculus of probability, endowed with a time dynamic, is indeed a calculus for causality. Pearl (1999) challenges this; he claims that (we must) deny the premise that causal relationships are governed by the laws of standard probability calculus. Lindley shares Pearl's claim; he feels that causality needs its own calculus so that users can operate with it as confidently as they do with the calculus of probability. In what follows, I hope to make my case.