Random TOS Tragic Musings

I'm rewatching Star Trek TOS again (as people have probably noticed), and I was rewatching "The Immunity Syndrome" last night. And something struck me about the conversation between Spock and McCoy before Spock heads out in the shuttle.

( Spock, it's probably a good thing you've no idea what you just said (warnings for death, self-sacrifice and euthanasia) )