# Definition:Parenthesis/Historical Note

Round brackets $\paren \;$ first appeared in $1544$.
Square brackets $\sqbrk \;$ and curly brackets $\set \;$ were used by François Viète in around $1593$.
1910: Alfred North Whitehead and Bertrand Russell: Principia Mathematica idiosyncratically use dots "$.$" for no immediate discernible benefit. The rules governing their use are complex and clumsy.