Semantics of non-existent objects

This thesis tackles the process of bringing together/aggregating the concepts of "non-existence" and "object". We tried to trace what has been left out of the definition of the object by considering what is called an object in the time period starting with the Parmenides's saying of "It is and it is not 'not to be'" until the present day. Intelligible in Plato and sensible in Aristotle were considered as basic and thereafter the definition of the object has been changed constantly in between what is intelligible and what is sensible. Ontological and metaphysical frames have been shaped accordingly. Kant who has been a necessary reference point for the later philosophers can be considered as the starting point of the process preparing the possibility of semantics of the non-existent objects in the modern period. After Kant's argument that object is not a thing on its own either in the intelligible or in the sensible realm but something that is constructed in intuition and/or pure intuition by giving unity to the representation with the joint employment of intellect and imagination, the idea that object is conceived by noesis was eliminate from the philosophical discourse. Along with the linguistic turn, it is argued that object is an entity constructed within language, as reminiscent of Kant's view; and thereafter object is always thought as a somehow constructed entity. Object viewed as not immediate intuited but as constructed requires an elucidation of the relation between language and thought and therefore between sense and reference. In this case, where the ontological and metaphysical positions of things which can be constructed in language or thought but lack any reference are; and what the possibility of talking meaningfully about such things/concepts is have become an important problem that needs to be solved. Although Meinong suggested in his Theory of Objects that existence and having a reference is not condition of being an object, it has not been easy to grasp and accept the gist of this theory. In the 19th and 20th centuries, there have been developments in the fields of mathematics and logic, which have supported Meinong's theory and make it possible to speak meaningfully about concepts lacking reference. Kripke's definition of accessibility relation and development of possible world semantics paved the way to talk meaningfully about objects that do not exist in the actual world but could possibly exist in another. Latest developments in modal logic also lead to talk about impossible objects whose acceptance is still a matter of debate. As of the current stage in logic and science, it seems that there are not many options to exclude non-existent objects which can be called as possible and / or impossible objects, into the justifiable object category. At the end of our study, we present a critical evaluation of classical metaphysics and suggest frame for a new metaphysical understanding.