A formula in which positive values represent infinity. There is no specific number, but positive infinity means a value greater than any number. The sign is +∞, and the sign of negative infinity is -∞.

Aristotle (384-322 BC), an ancient Greek philosopher, believed that infinity could exist, because a finite quantity was infinitely separable and could not reach the pole, but infinity was universally acknowledged as unreachable.

/kloc-in the 20th century, a great Indian mathematician, Bascara, appeared, and his concept was close to that of modern theorization. The symbol of infinity was first proposed by JohnWallis in his paper Arithmetic Infinity (published in 1655).