Logical quantifier
In 1879, Gottlob Frege created a notation for universal quantification. Unlike the modern notation, he would represent a universal quantification by writing a variable over a dimple in an otherwise straight line. Frege did not create a notation for existential quantification. Instead, he combined universal quantification and a number of negations to make an equivalent statement. Frege's use of quantification was not widely known until Bertrand Russell's 1903 Principles of Mathematics.