A little identity puzzle...Would you still be you?

A philosopher once invited us to imagine a great battleship belonging to Theseus. At some point a plank of wood on its deck became loose and in need of replacing. Nothing unusual or controversial right? Let's see...

Theseus wonders if his ship is the same ship as before, after having part of its structure replaced. Most intuitions answer yes as this point, all we've done is a little restoration. Well, suppose we replace another part, and then another, until the entire ship is composed of entirely new matter - No materials of the original ship have endured.

Do we still want to assert that this is the same ship as before? What does it even mean to say that it is the same ship? Isn't this paramount to asserting that something immaterial exists, that would survive this chopping and changing, that IS Theseus' ship?

Why should we even care about hypothetical ship maintenance Honestly, its amazing how relevant this is when we consider the human analogy...

Suppose you loose an arm or leg (I'm not sure why my analogies go so dark :P). Would you be the same person? Common sense intuition once again says yes. But at what point of removing body parts would you stop being 'you'?

A lot of philosophers, as is the tradition these days, demand that the part of the body keeping you essentially you, is the brain. We can see why, what with dementia, amnesia and trauma highlighting a deterioration of brain corresponding with a deterioration of mind.

So here's a thought for you. Suppose science has moved on a few years and now some tiny neurone or synapse within your brain can be swapped with an exact, functioning, silicone replacement. Would you still be you? And, by extension, lets hypothetically bit by bit replace your whole brain full of neurones and synapses with exact and functioning silicone replicas. If you're still you at this point we have created artificial intelligence....weird right?

For the 'your no longer you' camp - when did you end?

Maybe it was at the first point at which we fiddled with your brain and replaced old material for new material. Cue the response...does that mean we cease to be after receiving organ donation? Additionally, as every cell in our body is thought to have been replaced once every 7- 10 years...do we become a new person each time we are created from fresh matter?

Where on earth does our identity lie then? What makes you you and what makes Theseus' ship?

Whatever your answer I guarantee it will tie you in all kinds of philosophical knots....enjoy!