If you have not already done so, please read the Course Overview. Before launching into Section 1, let us familiarize ourselves with the technical course environment. The basic material of the "Principles of Human Action" course is presented in a carefully planned sequence, although some supplemental material may be included or skipped at the student's choice. Often such optional material provides clarifying details, which were omitted from the main presentation in the interest of brevity, but which you may wish to examine if the line of reasoning seems unclear. Optional material is indicated by a yellow rectangle:  . If you click upon the rectangle, a new secondary window opens, offering an "excursion" through the additional subject matter. To return to the main discussion, press the "Return" button that concludes the optional material. The course will occasionally reference earlier pages, which can be similarly displayed in a temporary secondary window.

The pages of the main course should be viewed in sequential order, in order that terms may be precisely defined and basic premises properly established before they are applied to more complex issues. To progress to the next page in sequence, click the green arrow that points to the right....