You're also conveniently ignoring the fact that correlational variables are still used as a starting point for further research in science. People who regurgitate the "Correlation does not equal causation" ignore the fact that much of scientific evidence IS based on correlational evidence. Even scientists in early days used to commit the opposite fallacy of completely dismissing correlation, thereby dismissing a bulk of important scientific evidence. I'm a researcher in Academia, so i know the historical mistakes in that area. I'm a strong advocate in encouraging people to explore correlations that will potentially lead to unearthing the causal mechanisms in stuttering research..