Philosophy 102 - 6.2.1 The Ship of Theseus

Consider the following thought experiment. Imagine a wooden ship owned by the hero Theseus. Within months of launching, the need to replace decking would be evident. The salt content of sea water is highly corrosive. Accidents can also happen. Within a common version of the thought experiment, the span of one thousand years is supposed. Throughout the span, it is supposed that the entire decking and wooden content of the ship will have been replaced. The name of the ship remains constant. But given the complete change of materials over the assumed time span, in what sense can we assert that the ship is the same ship? We are tempted to conceptualize identity in terms of persistence, but the Ship of Theseus challenges the commonly held intuition regarding how to make sense of identity.

Similarly, as our bodies develop from zygote to adult, cells die and are replaced using new building materials we obtain though food, water, and our environment. Given this, are we the same being as we were 10 or 20 years ago? How can we identify what defines ourselves? What is our essence? This section examines answers proposed by secular and religious systems of belief.

Write Like a Philosopher

Watch the video “Metaphysics: Ship of Theseus” in the series Wi-Phi Philosophy. You will find five possible solutions for making sense of the thought experiment. Pick one solution and explain why the chosen solution is the most salient. Can you explain how the strengths outweigh the stated objections—without ignoring the objections?

This lesson has no exercises.

The content of this course has been taken from the free Philosophy textbook by Openstax