Morphine plus placebo

If I'm giving a drug like morphine for pain, I'll say, "I'm going to order some morphine for your pain. It's going to help you feel a lot better."

The word "morphine" is quite powerful. Even if you know nothing else about it, you likely know that it is really strong. That in itself along with the assurance of a doctor has an effect, more than if I say nothing and the patient gets the same dose of the same drug.

But isn't pain about the body?

Aren't pain receptors physical?

What does this say about the mind-body connection?

How much of any drug's effect is placebo? 

Is the very idea of a drug a placebo?

How many studies adequately measure placebo effects?

How many of our diagnoses are actually nocebos in and of themselves?

Powerful questions that would change healthcare.