Probabilistic reasoning as developed by John Locke can provide the English teacher with a useful system for teaching the research paper since it consists of four major strategies for probing a subject: (1) the use of maxims or principles, (2) the framing of hypotheses, (3) the use of analogy, and (4) the reliance on authority. However, it is the fourth method that provides the underpinning of the freshman research paper. Because of the untrustworthiness of second-hand evidence, Locke outlined six specific criteria for weighing testimonies. Consideration of these criteria may promote the skepticism that student researchers almost entirely lack. The first criterion is the number of witnesses that report on a given incident, while the second is the integrity of the witnesses. The third criterion is the author's design, intention, and purpose or goal in writing the piece and presenting the evidence, and the fourth is the circumstances that gave rise to the discourse. The evaluation of these criteria requires the students to examine the historical and political contexts of the source to determine what motivated the author to produce the piece of writing. The fifth criterion requires students to examine the internal consistency of the document. Finally, the sixth criterion examines the contrary testimonies on the subject. By using these criteria, students can learn to analyze and evaluate sources rather than use them as support in the simple sense of the term. (HOD)