ABSTRACT
You may think that the concept of causation is obvious, but it may be the most important and difficult concept in philosophy and science. We are taught that correlation is not causation, but we are not taught what is causation. This is important because every environmental assessment has a causal question at its center. What caused this observed effect? What effects does or will this chemical cause? What concentration of this chemical will cause no significant effects? Causal assessments (Chapter 1) are at least as complex as risk assessments but are seldom recognized as distinct. This chapter presents only some basic principles of causal assessment and a few important approaches. I encourage you to obtain the open access book Ecological Causal Assessment (just Google the title). The history of causation is littered with different ideas of how we know a cause when we see it and even whether causes exist at all. Three fundamental concepts that are still in use are the associationist, interventionist, and counterfactual theories.
