Shea Zellweger

Zellweger died in Alliance, Ohio, on August 7, 2022, at the age of 96.

Zellweger’s background is a combination of formal education and extensive research in the fields of Psychology, Pedagogy, Semiotics and Logic. In 1949, Zellweger attended a summer seminar at the Institute of General Semantics with Alfred Korzybski. In 1949–52, still in the era of Robert M. Hutchins and the Great Books Program, he earned his undergraduate degree at the University of Chicago. In 1975–76, he spent a year at the Biological Computer Laboratory, University of Illinois at Urbana-Champaign, under the direction of Heinz von Foerster. In 1982, while on sabbatical leave at the Peirce Edition Project, in Indianapolis (IUPUI), he examined and carefully reordered a 900 page section of manuscripts written by Charles Sanders Peirce entitled “The Simplest Mathematics” (1902). In 1989, he served the Peirce Edition Project again when he added to the proper sequencing of specific sections of Peirce’s extensive manuscripts. These multidisciplinary experiences contributed to the development, over a forty-year period, of his X-stem Logic Alphabet. Zellweger has been a respected academic speaker and author, especially in the fields of Semiotics and Education.

Shea Zellweger (September 7, 1925 – August 7, 2022) was an American semiotician who served as Chair of the Psychology Department at the University of Mount Union from 1969 to 1992. Zellweger’s lifetime achievements and academic contributions to education continue to be significant. Zellweger was probably best known for his creation of a simpler and more mentally intuitive system of logic notation called the Logic Alphabet. The Logic Alphabet, also known as the X-stem Logic Alphabet (XLA), is a notation system that contains a unique and visually iconographic approach to learning and performing logic operations. Patents have been issued on its design in the United States, Canada and Japan.

Zellweger was born in Chicago, Illinois, on September 7, 1925. He received his Ph.D. in Experimental Psychology at Temple University in 1966. His doctoral dissertation focused on early visual stimulation experience and its later effects on discrimination learning.

Zellweger’s contribution to the field of logic is best demonstrated through his development of the X-stem Logic Alphabet (XLA). The XLA notation is a highly advanced extension of both Charles Sanders Peirce’s box-X notation (1902) and Warren Sturgis McCulloch’s dot-X notation (1942). It could be said that XLA (1961–62) is the evolutionary product of the comprehensive work of Peirce, McCulloch, and Zellweger, or PMZ as an acronym. The standard notation used today (dot Logical conjunction, vee Logical disjunction, horseshoe Material conditional representing and, or, if) is a lingering, overly abstract, unsystematically selected set of symbols that was primarily developed and used by Peano, Whitehead, and Russell, or by common acronym PWR. This already exposes the primary weakness. Dot, vee, horseshoe do not carry any information that identifies, specifies, and encodes the truth tables they represent, namely, TFFF, TTTF, and TFTT. In marked contrast, XLA is an intentionally engineered set of sixteen iconographic letter shape symbols specifically designed to improve the efficiency of learning and performing logical operations. Serving as a system of highly abbreviated mini truth tables, Zellweger’s claim is that XLA is not only much easier to learn. It is also much easier to use. In fact, when ten-base numerals are used without the abacus and when XLA is used without written laid out rows and columns of truth tables, ordinary operations in both notations are easier to perform during the act of computational writing.