I’ve been looking for this quote for a while from a 1989 movie called Skin Deep. It’s a conversation between the lead character and his psychiatrist:

Dr. Westford: Don’t you know by now that changing one’s basic character is next to impossible?
Zach: No. I don’t know that. Jesus, Doctor, if I thought I couldn’t change, I wouldn’t come see you in the first place.
Dr. Westford: I didn’t say that you couldn’t.
Zach: You just said it was impossible.
Dr. Westford: I said it was next to impossible.
Zach: Well, shit, Doctor. “Next to” isn’t that far removed.
Dr. Westford: If it were, there’d be no analysts.
Zach: Not an entirely unhappy prospect, Doctor.
Dr. Westford: Did I ever tell you the story about the scorpion and the frog?
Zach: No.
Dr. Westford: A scorpion who couldn’t swim asked the frog to carry him across the river on his back. The frog said, “Do you think I’m crazy? Halfway across the river, you’ll sting me and I’ll drown.” “That’s not reasonable,” said the scorpion. “If I sting you and you drown, I’ll drown too.” Frog thought about it, he said, “Climb on.” Halfway across the river, the scorpion stung the frog, and as the frog was drowning, he said to the scorpion, “But now you’ll drown too.” The scorpion said, “Yes. I know.” “That’s not reasonable,” said the frog, and the scorpion replied, “Reason has nothing to do with it. I’m a scorpion. It’s my character.”
Zach: You know what I feel like saying to you?
Dr. Westford: Yes. You feel like telling me to go fuck myself, and you probably will, because it’s your character.
Zach: See you next Tuesday.

I think I’m going to have to find a copy of that film.