What defines “Me”?

This speech is not an answer, and does not attempt to answer any questions. In fact, it simply raises questions for us to ponder over.

There is essentially 2 observable parts that make up anyone- the physical appearance, and the personality. For the sake of argument, we will ignore the existence of the soul as we can neither proof nor disproof its existence. Now here comes the difficult part: which of these do we accept as the person? Or is it the two combined? Let me explain with some scenarios.

Scenario 1: your significant other suffers from a car crash. He/she is bedridden, had half his/her face burnt off, crippled and is unable to move anything below his/her neck. Yet he/she maintains the same personality that you know: jovial, caring, selfless/hurtful, spiteful, whatever. In terms of physical appearance, he /she is essentially a different person. You cannot even recognize who this person is if he/she does not open his/her mouth. In terms of his/her personality, he/she remains unchanged. In other words, he/she is the same person in a different body. Now is that still your significant other? Most will say yes.

Scenario 2: your significant other suffers from another accident. He/she suffers minor scratches, but had a severe concussion, to the point where he/she has a different personality. That person is now completely changed in terms of personality, from jovial to grumpy, caring to violent etc. Now since we take it that the scratches completely heal, but the brain damage is permanent, we can safely say that he/she is essentially a different person in your spouse's body. Now is that still who you love? Many will still say yes.

Scenario 3: same as the first 2, except that now the person is both brain damaged and injured. Your spouse, who originally looked and acted like snow white or tom cruise, now looks and acts like the evil witch or the hunchback of Notre dame. Now it brings another question: is that still your spouse? Many will still say yes.

Scenario 4: your significant other suddenly comes up to tell you after being married for 10 years, that in fact he/she died 3 months after the marriage, but was cloned to completely replace him/her. The person is identical; every physical appearance is identical, even to the point of childhood injuries and mitochondrial DNA. Memories are implanted such that psychologically he/she is the same as well. Essentially, he/she is the same person in the same body. Now how many would agree that this is still the one they love, that this is still the same person they met over 10 years ago before they got married?

Now let me explain in detail why we will ignore the existence of the soul in each of the scenarios. Firstly, who are we to say that due to the crash, soul switching occurred somehow and thus another person's soul is in your spouse's body? What if during the accident, somehow the personality of twin brothers in the same car was switched? How do we know if it was simply due to chance that they personality changed in the direction of their brother and not that their souls switched? How will we know that somehow again, by implanting memories in that person, the soul was moved over to the new body?

Now before you change your answer to the fourth scenario, what if you accept that clone as your real spouse and your REAL spouse comes back because he/she never really died? Now what if scenario 1/2/3 happened to this REAL spouse? Who is your real spouse then?

What defines us? What that can be observed can be changed. Does that change the person? The questions have been asked. Now it is up to you to answer it.