Recently, Mr. Thepmontri Limpaphayom, claiming to be an “independent historian”, has sent an Open Letter to Mr. Abhisit Vejjajiva, Thai Prime Minister. To our knowledge, Mr. Thepmontri is also a political activist. So, the credibility of this historian is in question. Can he interpret the past following rigorous standards of critical inquiry? Can he vigorously assert before the public the integrity of the discipline? The following remarks may give the answers to these questions. 1. Mr. Thepmontri, a Thai political activist Mr. Thepmontri Limpaphayom has actively participated in Thai political activities at least since 2009. In September 2009, Mr. Thepmontri and eight other Thai “scholars” lodged a suit to Thai Civil Court accusing Prime Minister Hun Sen, Deputy Prime Ministers Sok An and Foreign Minister Hor Nam Hong of “violating the Thai people's rights and liberties under the Thai constitution by encroaching on the Preah Vihear temple and the disputed area around t...