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nominalism a step further. It is the belief that even physical objects exist as those physical objects only in name. They do not have an external existence outside of a human mind. A particular chair is a chair because we call it a chair, not because it has properties of being a chair. The ship of Theseus is whatever people call the ship of Theseus. There are no exact, agreed-on definitions of the ship of Theseus. I believe that extreme nominalism is correct because of the fact that there is so much disagreement about what constitutes a particular object. If there were exact definitions, presumably people would know about them. Another reason for believing in (extreme) nominalism is that any form of Platonism demands unnecessarily complicated metaphysics. Why do we need the supposed existence of an abstract entity or “tag” for every physical object? Such abstract entities serve no purpose.
    From the view afforded by extreme nominalism, it becomes apparent that the reason we cannot answer questions about the ship of Theseus or changes to human beings has nothing to do with linguistic limitations. It is not that we lack the right words or definitions of these concepts. There is also no epistemological problem—that is, it is not a lack of knowledge of the exact definition of the real ship of Theseus. Nor is it a problem of having some type of deeper knowledge of the ship of Theseus beyond its physical stimuli. 5 Rather, we are dealing with a question of existence. In philosophical parlance this is an ontological problem. A real ship of Theseus need not exist.
    It is interesting to note that with extreme nominalism, certain abstract objects, such as the number 42, have a clearer existence than physical objects such as ships. After all, we all agree about the many different properties of the number 42. If you take 42 and you subtract 1, you get 41 rather than 42. This is in stark contrast to subtracting planks from a ship.
    I have shown that the ship of Theseus is part of our culturally constructed universe. There are other objects in this constructed universe such as Mickey Mouse and unicorns. In fact, more people know about Mickey Mouse than about Theseus’ silly boat. Our friendly mouse is introduced to nearly every child, whereas only classics majors, philosophy majors, and privileged readers of this book know about Theseus. Furthermore, one can go to Disney World and actually see a physical manifestation of Mickey. You can even stub your toe against him (such actions are not recommended). In contrast, at present, we cannot find any trace of Theseus’ ship in the port of Athens. We are left with the obvious question: In what way is the ship more existent than Mickey Mouse?
    The resolution of the problems presented in this section is a challenge to the usual view of the universe. Most people believe that there are certain objects in the universe and that human minds call those objects by names. What I am illustrating here is that those objects do not really exist. What do exist are physical stimuli. Human beings classify and name those different stimuli as different objects. However, the classification is not always strict and vagueness prevails. 6
    3.2  Hangin’ with Zeno and Gödel
    Zeno of Elea (about 490–430 BC) was a great philosopher who was a student of Parmenides (early fifth century BC). Being a devoted student, Zeno promoted and protected his teacher from all criticism. Parmenides had the philosophical and mystical belief that the world was “one” and that change and motion were merely illusions that a person could see through with enough training. To demonstrate that Parmenides’ ideas are correct, Zeno proposed several thought experiments or paradoxes that showed that it is illogical to actually believe that the world is a “plurality” and not “one,” or that change and motion actually happen. In this section I will concentrate on four of those