Recently, the psychological implications of philosophical beliefs, such as the belief in free will, have been the subject of much investigation. For example, free will belief has been found to display a positive correlation with decision-making ability, expression of gratitude, and academic performance. The current study aims to further investigate a once-observed relationship between free will belief and positive mental health, while also incorporating beliefs in dualism and determinism, as advised by contemporary authors. Because no study has investigated these variables in a similar combination before, an exploratory approach is taken in analysis. Results provide no evidence of a relationship between mental health and free will belief, or belief in determinism. Belief in dualism was found to have a negative correlation with mental health. These results, and their implications for counselling and psychotherapy, are discussed.