Examining a counterfactual using a structural causal model involves three steps. The approach is valid regardless of the form of the model relationships (linear or otherwise).

• Abduct Apply abductive reasoning (logical inference that uses observation to find the simplest/most likely explanation) to estimate $u$, the proxy for the unobserved variables on the specific observation that supports the counterfactual.

• Act For a specific observation, use the do operator to establish the counterfactual (e.g., m=0), modifying the equations accordingly.

• Predict Calculate the values of the output (y) using the modified equations.