Philosophy for Children is an educational program designed to cultivate critical, creative, and caring thinking. Despite empirical research since the 1970s, there is no unified theoretical model that explains the causal structures behind the program's effectiveness. To address this gap, our study seeks to answer two key questions: (i) What variables are identified in empirical research into the effectiveness of Philosophy for Children? (ii) Which causal relationships can be postulated between these variables? Based on a review of seven published systematic reviews and meta-analyses and 83 empirical studies, we construct a directed acyclic graph (DAG) that illuminates the variables and their causal relations which impact the effectiveness of Philosophy for Children. Additionally, our study provides a detailed description on how to use this novel methodology to create a causal model from a systematic analysis of empirical research.