# PHILOSOPHY /// The Ship of Theseus


Theseus is an interesting character for architects. He is the one that, helped by Ariadne, solved the mystery of Dedaleus’ labyrinth in order to kill the Minotaur. However, another aspect can trigger our interest about this episode of the Greek Mythology: his boat exhibition after he came back to Athens.
Plutarch recounts this story as following:

The ship wherein Theseus and the youth of Athens returned had thirty oars, and was preserved by the Athenians down even to the time of Demetrius Phalereus, for they took away the old planks as they decayed, putting in new and stronger timber in their place, insomuch that this ship became a standing example among the philosophers, for the logical question of things that grow; one side holding that the ship remained the same, and the other contending that it was not the same.

This philosophical problem interrogates what makes an entity’s identity; its physical integrity as a whole or the conservation of its parts’ assemblage. The notions of parts lead us to Spinoza of course, but also to Leibniz who has been interested in the Ship of Theseus’ problem. His concept of Monads, as primary units composing the world are assembled in entities and conserve the property of this same entity as long as they compose relations with each others. According to Leibniz, (and put in the very simple way my architect’s understanding implies) it does not matter if those parts are not the original one as long as both entities share the same properties.

Japanese architectural tradition seems to consider things that same way as some Temples were rebuilt in an identical way after having burned down (like the Golden Temple in Kyoto) and some others are being rebuilt every twenty years since their original construction.
In a similar way, our body needs only one year to renew 98% of its composing matter without losing its physical integrity. This example is interesting in the fact that it introduces the problem of age and the evolution of some properties of this body which allow the identity to be preserved yet being involved in a continuous mutation.