A psychiatrist, an internist, a surgeon and a pathologist were duck hunting together. As they huddled in their blind, they saw a duck flying nearby. As only males were in season, they wondered aloud if it was indeed a drake that they saw. The psychiatrist said, "Well, what's really more important is the duck's state of mind: does he see himself as a drake, or does he identify with a female identity."

"No," the internist said, "we need to run several tests before we can identify this fowl as a drake. I'd need to obtain several blood tests plus a chest X-ray. The duck would return to my clinic in 7 to 14 days for his results."

The surgeon, hearing this, scoffed. He reached for his automatic shotgun and blasted the entire magazine load of shells at the duck, which dropped lifeless from the sky.

The surgeon turned to look at the pathologist and said, "Go examine that and tell me if it was a drake or not."