This document discusses different levels of analysis in social science and causation. It distinguishes between individual-level analysis, which focuses on individual decisions and behaviors, and aggregate-level analysis, which looks at higher-level groups and systems. Multilevel modeling is presented as a way to reconcile these approaches by including variables from both the individual and aggregate levels. The document also cautions against two fallacies - ecological fallacy of making inferences about individuals based on aggregate data, and atomistic fallacy of inferring higher-level relationships from lower-level data. This is illustrated using an example of migration patterns in Norway.