Your eyes are open, your ears are working: you see the ocean and hear the crash of the waves. But our senses are often subject to illusion, and sometimes even hallucination. How can perception give us knowledge of reality when it is notoriously unreliable? Is perception, instead, a veil that obstructs knowledge of the world around us? In this course, students will develop their academic writing skills by critically examining what is puzzling about illusion and hallucination, drawing on approaches and problems from philosophy and psychology.