Philosophy professor Peter Boghossian argues that reason and evidence are the only way to determine which "claims about the world are likely true". Different religious traditions make different religious claims, and Boghossian asserts that faith alone cannot resolve conflicts between these without evidence. He gives as an example of the belief held by that Muslims that Muhammad (who died in the year 632) was the last prophet, and the contradictory belief held by Mormons that Joseph Smith (born in 1805) was a prophet. Boghossian asserts that faith has no "built-in corrective mechanism". For factual claims, he gives the example of the belief that the Earth is 4,000 years old. With only faith and no reason or evidence, he argues, there is no way to correct this claim if it is inaccurate. Boghossian advocates thinking of faith either as "belief without evidence" or "pretending to know things you don't know".