“Perfect Arithmetic” by Vaclav Josef Pelikan

The present article describes for the first time the book of Vaclav Josef Pelikan titled Arithmeticus Perfectus Qui tria numerare nescit. Seu Arithmetica dualis, In qua Numerando non proceditur, nisi ad duo, & tamen omnes quaestiones Arithmeticae negotio facili enodari possunt, published in Prague in 1712. The book is written in Latin on 86 pages and consists of a dedication, a message to the reader and four chapters. Operations in the binary system, including the extraction of square and cube roots, methods of converting numbers from the decimal system to the binary system and vice versa, etc., are given. In general, we may say that the book by Vaclav Josef Pelikan is the first fully fledged and methodologically sound textbook of arithmetic using the binary number system as well as containing original methods of solution.