Dick H. J. de Jongh is a Dutch

Netherlands

The Netherlands is a constituent country of the Kingdom of the Netherlands, located mainly in North-West Europe and with several islands in the Caribbean. Mainland Netherlands borders the North Sea to the north and west, Belgium to the south, and Germany to the east, and shares maritime borders...

 logic

Logic

In philosophy, Logic is the formal systematic study of the principles of valid inference and correct reasoning. Logic is used in most intellectual activities, but is studied primarily in the disciplines of philosophy, mathematics, semantics, and computer science...

ian and mathematician

Mathematics

Mathematics is the study of quantity, space, structure, and change. Mathematicians seek out patterns and formulate new conjectures. Mathematicians resolve the truth or falsity of conjectures by mathematical proofs, which are arguments sufficient to convince other mathematicians of their validity...

 and a retired professor at the University of Amsterdam.
He received his PhD

Doctor of Philosophy

Doctor of Philosophy, abbreviated as Ph.D., PhD, D.Phil., or DPhil , in English-speaking countries, is a postgraduate academic degree awarded by universities...

 degree in 1968 from the University of Wisconsin–Madison

University of Wisconsin–Madison

The University of Wisconsin–Madison is a public research university located in Madison, Wisconsin, United States. Founded in 1848, UW–Madison is the flagship campus of the University of Wisconsin System. It became a land-grant institution in 1866...

 under supervision of Stephen Kleene

Stephen Cole Kleene

Stephen Cole Kleene was an American mathematician who helped lay the foundations for theoretical computer science...

 with a dissertation entitled Investigations on the Intuitionistic Propositional Calculus. De Jongh is mostly known for his work on proof theory

Proof theory

Proof theory is a branch of mathematical logic that represents proofs as formal mathematical objects, facilitating their analysis by mathematical techniques. Proofs are typically presented as inductively-defined data structures such as plain lists, boxed lists, or trees, which are constructed...

, provability logic

Provability logic

Provability logic is a modal logic, in which the box operator is interpreted as 'it is provable that'. The point is to capture the notion of a proof predicate of a reasonably rich formal theory, such as Peano arithmetic....

 and intuitionistic logic

Intuitionistic logic

Intuitionistic logic, or constructive logic, is a symbolic logic system differing from classical logic in its definition of the meaning of a statement being true. In classical logic, all well-formed statements are assumed to be either true or false, even if we do not have a proof of either...

. De Jongh is a member of the group collectively publishing under the pseudonym

Pseudonym

A pseudonym is a name that a person assumes for a particular purpose and that differs from his or her original orthonym...

 L. T. F. Gamut. In 2004, on the occasion of his retirement, the Institute for Logic, Language and Computation at the University of Amsterdam published a festschrift

Festschrift

In academia, a Festschrift , is a book honoring a respected person, especially an academic, and presented during his or her lifetime. The term, borrowed from German, could be translated as celebration publication or celebratory writing...

in his honor.

External links

• Web page at the University of Amsterdam