How the Human Brain Contends With the Strangeness of Zero

Around 2,500 years ago, Babylonian traders in Mesopotamia impressed two slanted wedges into clay tablets. The shapes represented a placeholder digit, squeezed between others, to distinguish numbers such as 50, 505 and 5,005. An elementary version of the concept of zero was born. Hundreds of years later, in seventh-century India, zero took on a new identity. No longer a placeholder…

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