I'd like to put in a vote for the intrinsic fascination of science.

Tatum and George Beadle who won for their work with genetics. Inspired by Oswald Avery's discovery of the importance of DNA Lederberg began to investigate his hypothesis that contrary to prevailing opinion bacteria did not simply pass down exact copies of genetic information making all cells in a lineage essentially clones. Laurance Morse Esther Lederberg and Joshua Lederberg also discovered specialized transduction.

Joshua Lederberg ForMemRS (May 23 1925 – February 2 2008) was an American molecular biologist known for his work in microbial genetics artificial intelligence and the United States space program. He shared the prize with Edward L. Tatum and George Beadle who won for their work with genetics.