JEVONS, ON THE MECHANICAL PERFORMANCE OF LOGICAL INFERENCE, 1870

4to, plates, original printed wrappers, Jevons's text unopened, modern folding cloth box, tears to first gathering and wrappers, one tear to one leaf of Jevons's text, spine defective, staining at beginning and end of text and to wrappers (slight staining to the three plates accompanying Jevons's text), slight foxing

bought from Biblion, 1983

Tomash & Williams J15; Origins of Cyberspace 330; Randell 1979 p.140

Condition is described in the main body of the cataloguing, when appropriate.
"In response to your inquiry, we are pleased to provide you with a general report of the condition of the property described above. Since we are not professional conservators or restorers, we urge you to consult with a restorer or conservator of your choice who will be better able to provide a detailed, professional report. Prospective buyers should inspect each lot to satisfy themselves as to condition and must understand that any statement made by Sotheby's is merely a subjective, qualified opinion. Prospective buyers should also refer to any Important Notices regarding this sale, which are printed in the Sale Catalogue.
NOTWITHSTANDING THIS REPORT OR ANY DISCUSSIONS CONCERNING A LOT, ALL LOTS ARE OFFERED AND SOLD AS IS" IN ACCORDANCE WITH THE CONDITIONS OF BUSINESS PRINTED IN THE SALE CATALOGUE."

JEVONS'S LANDMARK PAPER PRESENTING HIS MACHINE FOR LOGICAL INFERENCE, HIS "LOGICAL PIANO", THE FIRST MACHINE WITH ENOUGH POWER TO SOLVE COMPLICATED PROBLEMS WITH SUPERHUMAN SPEED. Jevons had been working on a "reasoning machine, or logical abacus" (Papers, 4.69) since 1865. The machine had piano-like keys for entering the terms of the logical elements and Jevons had it constructed by a Salford clock-maker (for a full description see Buck and Hunka, "W. Stanley Jevons, Allan Marquand, and the Origins of Digital Computing", Annals of the History of Computing, Vol.21, No.4, 1999, pp.21-27). Despite Jevons's fear that it might be laughed at it was in fact much admired when exhibited at the Royal Society in 1870 since it was able to solve logical problems with extraordinary, superhuman speed. The machine, one of the key precursors of the modern computer, is preserved at the Oxford Museum of the History of Science.

"...it will be evident that mechanism is capable of replacing for the most part the action of thought required in the performance of logical deduction..."