Origin of the Infinity Symbol
Date: 20 Jan 1995 17:47:00 -0500 From: Betty Thompson Subject: math symbol I need to find the origin of the math symbol for infinity that is used today. It looks like an 8 lying on its side. Betty Thompson Taylor Public Library Taylor, TX 76574 firstname.lastname@example.org
Date: 24 Jan 1995 00:41:39 GMT From: Dr. Math Subject: Re: math symbol Hello there! I looked this one up in a book called "A History of Mathematical Notations" by Florian Cajori. He credits the English mathematician, John Wallis, with inventing the modern notation for infinity. And I quote: "Cum enim primus terminus in serie Primanorum sit 0, primus terminus in serie reciproca erit [infinity symbol] vel infinitus." I don't read Latin, but I think that what he was trying to do is give a definition of infinity, and then introduce his new symbol. It looks like he was talking about sequences and all that stuff. He alludes to the fact that if a sequence goes to zero, then the sequence of reciprocals will go to infinity. The work which he wrote this in was called "Arithmetica infinitorum," which was published in 1655. This notation also appears in his book "De Sectionibus Conicis."
Search the Dr. Math Library:
Ask Dr. MathTM
© 1994- The Math Forum at NCTM. All rights reserved.