Person: Aristaeus the Elder
Aristaeus the Elder was a Greek mathematician who worked on conic sections.
Mathematical Profile (Excerpt):
 We know practically nothing of his life except that Pappus refers to him as Aristaeus the Elder which presumably means that Pappus was aware of another later mathematician also named Aristaeus.
 We have no record of such a person but we do point out below a possible confusion which may result from there being two mathematicians called Aristaeus.
 Pappus gave Aristaeus great credit for a work entitled Five Books concerning Solid Loci which was used by Pappus but has now been lost.
 'Solid loci' is the Greek name for conic sections so it is rather confusing that there is another reference by a later writer to a work by Aristaeus called Five Books concerning Conic Sections.
 and also claims (if this is not a latter addition to the text) that Euclid compiled elementary results on conics in his treatise Conics while Aristaeus's results, much deeper, original and specialised, were not included by Euclid who preferred to leave them in their original presentation due to Aristaeus.
 But it may be assumed that Aristaeus's work was not merely a collection of the ordinary propositions transformed in this way; it would deal with new locus theorems not implied in the fundamental definitions and properties of the conics, such as ...
 There is a reference to Aristaeus in the works of Hypsicles where he refers to Aristaeus as the author of a book Concerning the Comparison of Five Regular Solids.
 Heath believes that, although it is not certain whether this is Aristaeus the Elder, the results described make it quite probable that it is.
 Heath's opinion that the Aristaeus referred to by Hypsicles this is Aristaeus the Elder has been disputed by some historians, and there is a possibility that Hypsicles refers to Aristaeus the Younger thus making sense of Pappus's comments which we referred to in the first paragraph.
 The work of both Aristaeus and Euclid on conics was, almost 200 years later, further developed by Apollonius.
 This work by Apollonius made the theory of conics as developed by Aristaeus and Euclid obsolete.
Born about 370 BC, Greece. Died about 300 BC.
View full biography at MacTutor
Tags relevant for this person:
Ancient Greek, Origin Greece
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References
Adapted from other CC BYSA 4.0 Sources:
 Oâ€™Connor, John J; Robertson, Edmund F: MacTutor History of Mathematics Archive