a German mathematician

David Hilbert (January 23, 1862, Königsberg, East Prussia – February 14, 1943, Göttingen, Germany) was a German mathematician, recognized as one of the most influential and universal mathematicians of the 19th and early 20th centuries.

a 20th century mathematician

David Hilbert is a 20th century mathematician, and was chosen as the judge because David Hilbert is famous in part for Hilbert's Problems.

a German mathematician, logician, and philosopher of mathematics

David Hilbert (Königsberg,[1] Prussia, 23 January 1862 –Göttingen, Germany, 14 February 1943) was a German mathematician, logician, and philosopher of mathematics.