Ternary computers use three-valued logic in their calculations. History has several examples of this form of computing. A ternary, three-valued or trivalent logic is a term to describe any of several multi-valued logic systems in which there are three truth values indicating true, false and some third value. ...

One of the earliest calculating machines, built by Thomas Fowler entirely from wood in 1840, was a ternary computer. The largest-yet ternary computer (called Setun) was built in the late 1950s in the Soviet Union at the Moscow State University, and it had notable advantages to the binary computers which eventually replaced it. Thomas Fowler (born 1777 in Great Torrington, Devon, England - died March 31, 1843) was a British inventor whose most notable invention was the thermosiphon which forms the basis of most modern central heating systems. ... 1840 is a leap year starting on Wednesday (link will take you to calendar). ... Setun (Russian: ) was a balanced ternary computer developed in 1958 in Russia. ... Moscow State University M.V. Lomonosov Moscow State University (Russian: Московский государственный университет имени М.В.Ломоносова, often abbreviated МГУ, MSU, MGU) is the largest and the oldest university in Russia, founded in 1755. ... The binary numeral system (base 2 numerals) represents numeric values using two symbols, typically 0 and 1. ...

With the advent of mass-produced binary components for computers, ternary computers have diminished to a small footnote in the history of computing. However, ternary logic's elegance and efficiency is predicted by Donald Knuth^{[citation needed]} to bring them back into development in the future. Donald Knuth at a reception for the Open Content Alliance. ...

Ternary computing is commonly implemented in terms of balanced ternary, which uses the three digits -1, 0, and +1. The negative value of any balanced ternary number can be obtained by replacing every + with a – and vice versa. It is easy to subtract a number by inverting the + and – digits and then using normal addition. Balanced ternary can express negative values as easily as positive ones, without the need for a leading negative sign as with decimal numbers. These advantages make some calculations more efficient in ternary than binary. Balanced Ternary (aka Signary) is a method of numeric representation which expands on binary and is similar to trinary. ...

"I often reflect that had the Ternary instead of the binary Notation been adopted in the Infancy of Society, machines something like the present would long ere this have been common, as the transition from mental to mechanical calculation would have been so very obvious and simple." (Fowler, 1840)

See Also

• Ternary logic
• Ternary numeral system
• Balanced Ternary
• Setun

A ternary, three-valued or trivalent logic is a term to describe any of several multi-valued logic systems in which there are three truth values indicating true, false and some third value. ... Ternary or trinary is the base-3 numeral system. ... Balanced Ternary (aka Signary) is a method of numeric representation which expands on binary and is similar to trinary. ... Setun (Russian: ) was a balanced ternary computer developed in 1958 in Russia. ...

External links

• Development of ternary computers at Moscow State University
• The ternary calculating machine of Thomas Fowler
• Trinary.cc - logic gates used to build a ternary computer