Reasoning is the process of generating conclusions from evidence or premises. There are different types of reasoning including inductive reasoning which allows humans to make generalizations from their environment, deductive reasoning which applies generalizations, sign reasoning which draws conclusions from signs, reasoning from authority which argues claims based on credible sources, comparison reasoning which links similarities between things, figurative comparison which links similarities metaphorically, and literal comparison which establishes links between similar classifications. The critical thinker must remember to validate the reasoning used to establish conclusions.