John von Neumann: an outstanding mathematician as well as the prominent representative of the mathematical, theoretical and applied sciences whose contributions in such areas as physics, computer science, and haematology have been invaluable for the further development of the modern world. Evan from Budapest, Hungary in 1903, people of all ages knew that there was something special about von Neumann.

His work in mathematics contributed to the great development of set theory, functional analysis, and quantum mechanics. However, he is potentially best remembered for the important role he played in computer science and the creation of the modern computer.

Alonzo Church developed the concept of a lambda defnition, which defines a particular function and is the basis for many current computer structures, and John von Neumann put forth a plan of structure for efficient digital computers that store data and programs in the same memory, for the most modern computers.

Furthermore, he made a significant contribution towards the development of game theory that premised the rational behavior amid uncertain economic environments.

Another area of contribution by Von Neumann was in the Manhattan project, which involved construction of nuclear weapons during the second world war.

His visionary ideas and decision to work with students from different fields keep inspiring many scientific and technological disciplines in the 21st century, thus giving Niklas Luhmann the right to be considered one of the key thinkers of the twentieth century.