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Throughout the history of mankind,
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three little words have sent poets
to the blank page,
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philosophers to the Agora,
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and seekers to the oracles:
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"Who am I?"
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>From the ancient Greek aphorism
inscribed on the Temple of Apollo,
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"Know thyself,"
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to The Who's rock anthem, "Who Are You?"
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philosophers, psychologists, academics,
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scientists, artists,
theologians and politicians
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have all tackled the subject of identity.
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Their hypotheses are widely varied
and lack significant consensus.
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These are smart, creative people,
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so what's so hard about coming up
with the right answer?
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One challenge certainly lies
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with the complex concept
of the persistence of identity.
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Which you is who?
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The person you are today?
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Five years ago?
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Who you'll be in 50 years?
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And when is "am"?
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This week?
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Today?
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This hour?
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This second?
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And which aspect of you is "I"?
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Are you your physical body?
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Your thoughts and feelings?
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Your actions?
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These murky waters of abstract logic
are tricky to navigate,
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and so it's probably fitting
that to demonstrate the complexity,
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the Greek historian Plutarch
used the story of a ship.
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How are you "I"?
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As the tale goes, Theseus, the mythical
founder King of Athens,
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single-handedly slayed
the evil Minotaur at Crete,
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then returned home on a ship.
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To honor this heroic feat,
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for 1000 years Athenians painstakingly
maintained his ship in the harbor,
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and annually reenacted his voyage.
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Whenever a part of the ship
was worn or damaged,
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it was replaced with an identical piece
of the same material
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until, at some point,
no original parts remained.
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Plutarch noted the Ship of Theseus
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was an example
of the philosophical paradox
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revolving around
the persistence of identity.
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How can every single part
of something be replaced,
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yet it still remains the same thing?
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Let's imagine there are two ships:
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the ship that Theseus
docked in Athens, Ship A,
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and the ship sailed by the Athenians
1000 years later, Ship B.
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Very simply, our question is this:
does A equal B?
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Some would say that for 1000 years
there has been only one Ship of Theseus,
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and because the changes made to it
happened gradually,
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it never at any point in time
stopped being the legendary ship.
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Though they have absolutely
no parts in common,
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the two ships are numerically identical,
meaning one and the same,
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so A equals B.
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However, others could argue
that Theseus never set foot on Ship B,
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and his presence on the ship
is an essential qualitative property
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of the Ship of Theseus.
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It cannot survive without him.
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So, though the two ships
are numerically identical,
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they are not qualitatively identical.
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Thus, A does not equal B.
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But what happens
when we consider this twist?
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What if, as each piece
of the original ship was cast off,
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somebody collected them all,
and rebuilt the entire original ship?
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When it was finished, undeniably
two physical ships would exist:
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the one that's docked in Athens,
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and the one in some guy's backyard.
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Each could lay claim to the title,
"The Ship of Theseus,"
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but only would could actually
be the real thing.
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So which one is it,
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and more importantly,
what does this have to do with you?
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Like the Ship of Theseus,
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you are a collection of constantly
changing parts:
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your physical body, mind, emotions,
circumstances, and even your quirks,
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always changing, but still in an amazing
and sometimes illogical way,
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you stay the same, too.
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This is one of the reasons that
the question, "Who am I?" is so complex.
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And in order to answer it,
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like so many great minds before you,
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you must be willing to dive into the
bottomless ocean of philosophical paradox.
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Or maybe you could just answer,
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"I am a legendary hero sailing
a powerful ship on an epic journey."
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That could work, too.
