Nicomachus (Greek: Νικόμαχος) (c. 60 – c. 120) was an important mathematician in the ancient world and is best known for his works Introduction to Arithmetic (Arithmetike eisagoge) and Manual of Harmonics in Greek. He was born in Gerasa, Roman Syria (now Jerash, Jordan), and was strongly influenced by Aristotle. He was a Pythagorean.
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Nothing is known about the life of Nicomachus except that he was a Pythagorean and that he came from Gerasa. The age in which he lived (c. 100 AD) is only known because he mentions Thrasyllus in his Manual of Harmonics, and because his Introduction to Arithmetic was apparently translated into Latin in the mid 2nd century by Apuleius. As a NeoPythagorean, Nicomachus was often more interested in the mystical properties of numbers rather than their mathematical properties.
Introduction to Arithmetic (Greek: Ἀριθμητικὴ εἰσαγωγή), the lesser work on arithmetic. Nicomachus writes extensively on numbers, especially on the significance of prime numbers and perfect numbers and argues that arithmetic is ontologically prior to the other mathematical sciences (music, geometry, and astronomy), and is their cause. Boethius' De institutione arithmetica is in large part a Latin translation of this work.
Manual of Harmonics (Greek: Ἐνχειρίδιον ἁρμονικῆς). This is the first important music theory treatise since the time of Aristoxenus and Euclid. It provides the earliest surviving record of the story of Pythagoras's epiphany outside a smithy that pitch is determined by numeric ratios. Nicomachus also gives the first in depth account of the relationship between music and the ordering of the universe via the "music of the spheres." Nicomachus's discussion of the governance of the ear and voice in understanding music unites Aristoxenian and Pythagorean concerns, normally regarded as antitheses.^{[1]} In the midst of theoretical discussions, Nicomachus also describes the instruments of his time, also providing a valuable resource. In addition to the Manual, ten extracts survive from what appear to have originally been a more substantial work on music.
The works which are lost are:

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Categories: Disambiguation
Nicomachos or Nicomachus is a Greek name. It can mean:
