# Paul Werbos
**Domain:** Machine Learning / Systems Modeling / Optimization
**Doc Type:** Person Node
**Maturity:** Foundational
## Definition
**Paul J. Werbos** is a scientist whose 1974 Harvard dissertation developed backward derivative propagation through composed nonlinear operations and connected that machinery to adaptive systems.
## Historical Context
Werbos called the procedure **dynamic feedback** and described computing derivatives by proceeding backward through an ordered table of differentiable operations. His 1981 conference contribution, published in 1982, treated backward differentiation in neural-network training.
## Sources / Provenance
- Paul J. Werbos, _Beyond Regression_, 1974.
- Paul J. Werbos, “Applications of Advances in Nonlinear Sensitivity Analysis,” 1982.
## See Also
[[wiki/Reverse-Mode Automatic Differentiation|Reverse-Mode Automatic Differentiation]], [[wiki/Backpropagation|Backpropagation]], [[wiki/Seppo Linnainmaa|Seppo Linnainmaa]]