Cogitans is not a word used nowadays. It literally means “thinking” in Latin. But it has an elegant history in philosophy (the work of Rene Descartes) as part of longer phrases. For example, res cogitans (res means material or stuff in Latin) represents the mental substance while res extensa meant the material brain. These were the two parts of the famous mind:body duality so crucial to many worldviews. As we stated in the Intro to this section, Al studied and collected many works and insights on “thinking.” He wrote a notebook of 238 pages (the size of a book) on what he called “Cogitans.” Excerpts follow: