Twelve Cognitive Processes That Underlie Learning 57 easy and requires a level of abstraction that is very important to learn. Most creative thinking depends on this ability to abstract plans from one field of knowledge to another. We learn to do this by practicing it. Teachers can help people see correspondences across domains. Ab- straction of this sort is what creative people do best. 3. Causation: Detecting what has caused a sequence of events to occur by relying on a case base of previous knowledge of similar situations (case-based reasoning) All fields of knowledge study causation; biology, physics, history, economics—they are all about what causes what. The fact that this is an object of study by academics tells us right away that it is not easy and no one knows for sure all of the causes and effects that there are in the world. Because of this, acquiring a set of known causes and effects tends to make one an expert. A plumber knows what causes sinks to stop up and knows where to look for the culprit. A mechanic knows what causes gas lines to leak and knows where to look. A detective knows what causes people to kill and knows where to start when solving a murder case. Causal knowledge is knowledge fixed to a domain of inquiry. Experts have extensive case bases. Case bases are acquired by starting on easy cases and graduating to more complex ones. It is im- portant to discuss with others the cases one works on because this makes one better at indexing them in one’s mind, enabling one to find them later as needed. 4. Judgment: Making an objective judgment There are two forms of this, both involving decisions based on data. The first is deciding whether you prefer Baskin Robbins or Ben and Jerry’s. There is no right answer. We make judgments and then record them for use later. We find ways to express our judgments (Ben and Jerry’s is too sweet, for example). We learn what we like by trying things out. A wine expert learns about wine by drinking it and recor