How do rule-based models represent thinking with “IF…THEN…” instructions?

In the context of the philosophy of mind and cognitive science, rule-based models represent thinking as a process of symbol manipulation based on inference rules.1

These models posit that thinking consists of applying "IF…THEN…" instructions to complex symbols that possess an internal structure similar to natural language sentences. The process functions as follows:1

• Symbol Processing: The system takes an initial symbol (representing a state or belief) and applies a rule to it.1
• Logical Derivation: If the input matches the "IF" condition, the system generates a new symbol defined by the "THEN" consequence.1
• Sequential Application: The output of one rule often serves as the input for the next, allowing the system to chain inferences together to model complex tasks like problem solving or language use.1

For example, the rule "IF you eat too much, THEN you will have a stomach ache" transforms the symbol "you ate too much" into the symbol "you will have a stomach ache," which can then trigger subsequent rules. This approach treats the mind as a computational system where reasoning is a series of mechanical, step-by-step derivations.12