On the Consistency Rule in Causal Inference Axiom, Definition, Assumption, or Theorem? (Pearl, 2010, 4 page) One of the big problems with the causality literature is the terminology and the lack of foundationas for everyone to agree on.(Think about a vector space -- everyone agrees what it is. That's where we want to be.) The consistency rule appears to me to be the corner-stone of an axiomatic development of causality theory.
The following papers are mentioned in the Pearl paper and are a part of the assignment:
An Axiomatic Characterization of Causal Counterfactuals (Galles, Pearl, 1998, 27 p) This is a formalization of the counterfactuals using terms of logic. It does not look very difficult, i.e. you don't need much logic to understand what's going on (the terms "sound" and "complete" notwithstanding.) I skimmed it about half a year ago and I believe there is room for extending substantially on this work.
The Causal Foundations of Structural Equation Modeling (Pearl, 2012, 37 pages) This is about the connection between Pearl's work and structural equation modeling. Obviously good to read you work with SEMs, might be boring if not?
Causes and Explanations: A Structural-Model Approach. Part I: Causes (Halpern, Pearl, 2005, 45 small pages) Published in a philosophy of science journal. Probably good reading if we want to or need to engage with philosophy at some point. Both are probably true for me. The paper has a second part, "explanations".