Throughout history, thinkers across philosophy, mathematics, science, and literature have developed critical thinking skills that help us judge the value of information. These are distilled into six memorable steps, each tied to the first six letters of the alphabet: A is for Argument, B for Bias, C for Context, D for Diagram, E for Evidence, and F for Fallacies. Together, these tools guide clearer reasoning and more meaningful discussions on any topic. What you think is up to you. But there are specific rules that govern better and worse ways regarding ‘how’ we think.