Harry Potter and the Methods of Rationality is an alternate universe Harry Potter fanfiction written by Eliezer Yudkowsky, an AI researcher and decision theorist at the Singularity Institute for Artificial Intelligence. The story focuses on a Harry Potter who enters Hogwarts after having been raised with an Aunt Petunia who married a scientist. The fanfiction is known for possibly being the most reviewed Harry Potter fanfiction, with over 20,000 reviews on Fanfiction.net as of 29 June, 2013.