Seeing Pink Elephants: A phenomenological assessment of the debate concerning visual hallucinations between philosophy of mind and psychiatry

The purpose of this master's thesis is to clarify the understanding of hallucinations in many of the opposing positions in the panorama of contemporary philosophy of mind by arguing that perceptions and hallucinations are mental events of different kinds in some respects. In light of the objectives of my master’s thesis, I will refer only to philosophical (or total or perfect) and psychiatric visual hallucinations. Furthermore, since hallucinations and perceptions are often referred to as subjectively distinguishable or indistinguishable, I will to deepen the role of the subject as well. When we say that in a hallucinatory state it is not subjectively possible to distinguish between perception and hallucination, what does that ‘subjectively’ mean? In what situation is it possible to distinguish or not subjectively? There are many ways in which it can be expressed. This is why the other purpose of this master's thesis is to determine whether the subject who experiences hallucinations and perceptions can distinguish between the two and whether it is possible to assert that the subject can in principle not distinguish hallucinations and perceptions. After explaining the terminology I will use to describe perceptions, illusions, and hallucinations, I will examine how various advocates of the Common Kind Conception (CKC), such as sense-data theorists, advocates of advertising and representation, as well as some advocates of disjunctivism, address the case of hallucinations. Furthermore, the examination of the evolution of the hallucinatory symptom in psychiatry will serve two purposes: on the one hand, I think it is important to demonstrate the phenomenon's empirical foundation; on the other, I want to call attention to the fact that there is not a clear description that can effectively capture the intricacy of the hallucinatory experience. Given the fact that the psychiatric field does not seem to offer any particularly satisfactory or complete answer regarding the understanding of hallucinations, starting from some of Husserl's writings, I will also analyze the essential characteristics and the overall structure of perception, phantasy, and memory, focusing in particular on the distinction between sensations and phantasmata and on the role played by the Auffassung. Finally, I will start from the Husserlian-phenomenological analysis and apply it to the highly debated question underlying the conjunctivist and disjunctivist positions, through some cases of real psychiatric hallucinations. I will stand with a disjunctivist position, arguing that veridical perceptions and hallucinations are not experiences of the same fundamental kind and that if hallucinations and veridical perceptions are to share something, that something might be at most sensory data.