Simplify the following text for a Grade 9 native English-speaking person.
Original: David Hilbert ( KÃ nigsberg , Prussia , 23 January 1862 â `` GÃ ttingen , Germany , 14 February 1943 ) was a German mathematician .
Simplified: David Hilbert ( ; January 23 , 1862 -- February 14 , 1943 ) was a German mathematician .