Spock: I'm not hungry, Doctor. And under stress, we Vulcans can do without sleep for weeks.
McCoy: Well, your Vulcan metabolism is so low it can hardly be measured, and as for the pressure, that green ice water you call blood...
Spock: My physical condition is not important, Doctor. That obelisk is.
McCoy: Well, my diagnosis is exhaustion brought on from overwork and guilt. You're blaming yourself for crippling this ship Just as we blamed you. Well, we were wrong. So were you. You made a command decision. Jim would have done the same.