https://en.wikipedia.org/wiki/Ship_of_Theseus

There are a few main ways to approach this:

This isn't just about ships; it applies to anything that changes its parts. For example, your own body is constantly replacing its cells, yet you still feel like you.

• Identity by Components: Is an object's identity defined by its constituent parts? If all parts change, is the object still the same?
• Identity by Form/Structure: Does the arrangement or form of the parts matter more than the parts themselves? If the structure remains, is it the same?
• Identity by Function/History: Does what an object does or its history and purpose define its identity?

The Ship of Theseus is a classic philosophical problem that has been around for over two millennia. It's used to explore the concept of identity over time. The basic scenario involves a legendary ship whose planks are gradually replaced as they rot. Once every single plank has been replaced, the question arises: is it still the same Ship of Theseus?

This single question immediately brings up two main ways to think about identity: