The Commens Dictionary
Quote from ‘Chapter IV. Of Reality’
The reality must be connected with [the] chain of reasoning at one or other extremity. According as we place it at one end or the other, we have realism or nominalism.
The reality must be so connected with our thought that it will determine the conclusion of true investigation. But the conclusion depends on the observations. Reality must then be connected with sensation as its cause (or to use another phrase, as its possibility) and this is the nominalistic theory of reality.
‘Nominalism’ (pub. 03.04.15-16:54). Quote in M. Bergman & S. Paavola (Eds.), The Commens Dictionary: Peirce's Terms in His Own Words. New Edition. Retrieved from http://www.commens.org/dictionary/entry/quote-chapter-iv-reality.