The use of logic is an integral part of mathematical reasoning and communication. This exploratory study explored the reasoning by 122 science students from a university in Lesotho about the truth or falsity of conditional statements. Written tasks and interviews were used as methods of data collection to produce qualitative data. The tasks required the students to classify the given conditional statements as either true or false and explain their answers. The word 'explain' carried the meaning that students should provide reasons for their choice of answers. The analysis took into account whether students classified the statements correctly and if the reasons they gave resonated with their choice of answers. The findings of the study revealed that the majority of students correctly classified the statements as either true or false. What became of great interest was that most students classified the statements and their converses and their equivalences correctly with appropriate reasoning. Very few students could not give proper mathematical reasoning for their choice of answers. Implications for the findings of the study for teaching and future research are provided.