Prehistory — From Neural Networks to the TransformerGeorge Cybenko
Approximation by superpositions of a sigmoidal function
Approximation by superpositions of a sigmoidal function — proved the universal approximation theorem
Why it matters
Proved that a single hidden layer can approximate any continuous function, providing a theoretical basis for expressive power
Source — Primary sources first; secondary reports are labelled “Press”
Officiallink.springer.comhttps://link.springer.com/article/10.1007/BF02551274Added in Week 35, 2026 · See that week