Conway's Game of Life is Turing complete, so if it is possible to build an artificial intelligence in a regular computer then it is possible to build one within the Game of Life. Also, understanding the basic rules of the game of life is not the same as understanding how an artificial intelligence within it functions. The rules that determine how patterns of pixels change in the game can be written down on a single sheet of paper, a description of an artificial intelligence built within the game would probably be absurdly complex.