Why do people refer to Larry as 'Doc'?

On Inherent Vice, the protagonist is called Larry, but everyone calls him 'Doc'?

Why do they do that?

At first I thought he was actually a doctor (a stoned one), but then I saw he was working as a Private Investigator.

Best Answer

The given nickname is explained in the book.

When Larry 'Doc' Sportello was out of college, he had many debts to pay; back then he was simply known as Larry. The agency came after him and decide to hire him as a skip-tracer trainee to work his debt off. One of the things he had to do was to intimidate people to pay money they owed and he was allowed to carry a weapon; not a gun, but a truth-serum of some kind.

When he was interrogating people, they saw it and were afraid. It never became the tool of his trade, but it got him the nick name 'Doc'.

Exact quote:

"What - kind of 'weapon' is that?"
"It's a hypodermic outfit"
"I knew that, but what am I supposed to load it with?"
"Truth serum. Same kind the CIA uses. [...]

Larry decided to stash the outfit in a sinister-looking red faux crocodile shaving kit [...] many of the delinquents he and Fritz visited couldn't keep their eyes off of it. [...] It never quite became a tool of his trade, but did develop into a useful prop, in time earning him the nickname 'Doc'.

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