If anyone is looking for a relatively simpler explanation of GIT than Gödel's own work, I suggest the beautiful but sometimes inscrutable book "Gödel, Escher, B

If anyone is looking for a relatively simpler explanation of GIT than Gödel's own work, I suggest the beautiful but sometimes inscrutable book "Gödel, Escher, Bach" by Douglas Hofstadter. Hofstadter draws lines between the math, art, and music of these three giants of human creation, and it's a lot easier to read than anything written directly by Gödel. Roger Penrose's "The Emperor's New Mind" also has some good material on GIT.