In this talk Roland Poellinger (Munich) gives an outline of Judea Pearl's deterministic approach towards causation (workshop "Concrete Causation", 9 July, 2010). The title of the talk is taken from the programmatic section 2.2 of Pearl's paper "Causal Diagrams for Empirical Research" (Biometrika, Vol. 82, No. 4, 669-709, 1995) which is briefly sketched and commented on as an introduction to Pearl's interventionist account of causal analysis. Further topics: The problems of simple causal networks, interventions as variables, Humphreys' paradox, and causal decision making.