What makes you yourself? When are you no longer yourself? Is it in your physical body that resides your identity? If so, all amputees would lose a part of their identity. Is it your memories that make up who you are? If so, every time you forget something, your identity changes. So what are your theories on The Ship Of Theseus?
If you were a surgon and you had 5 patients come in, each needing an organ transplant but no donors were matched, what is the ethical choice? There are two obvious options, either sacrifice yourself for your patients or leave them all to die. But wouldn't the most ethical action be to sacrifice one patient for the others?