This statement borrows heavily from Umberto Eco who applied it to books and authors. It works more readily I think, with cartoons and cartoonists because it works as a negative as well as a positive. Here are two examples:
1. As a kid I looked at the drawings in my comics and I wanted to draw like that, so much so that I copied the drawings. In this sense the cartoon, the work of the cartoonist, inspires me to create my drawings.
2. As a teenager I would look at the cartoons in the Weekly News, and other publications, and think 'I can draw better than this, I should do this'. Again I am inspired to create a cartoon, even though my reasoning is, initially (but with the bravado of youth), negative.
What reinforced this theory, for me at least, was the declaration by a lot of US cartoonists that they subscribe to a publication called GAG RECAP, that lists every cartoon printed that month, (it doesn't show the cartoon, it describes it, and lists the punchline) and they use the punchlines as 'springboards' for thinking up their own new cartoons.
We don't have GAG RECAP over here, but I recognised the process from something that cartoonist David Langdon spoke of as 'creative mind wandering' where a news article, or an object, or a cartoon, or a joke, would set him off thinking 'what if'? It's also similar to a process that Robert Mankoff, the New Yorker Cartoon Editor describes in his book The Naked Cartoonist where one thinks of a subject, say psychiatry, and then wonders, 'what if a dog was a psychiatrist'. To me, the process seems to work like a form of controlled free-association (I'm aware of the oxymoron) - where you have the most obvious association with a current cartoon that perhaps features a male psychiatrist talking to another male and the cartoonist thinks 'hey, what if the psychiatrist here was a woman'(this is known in the cartooning business as 'switching' and it's pretty much frowned upon as a bit of a cheat) - not really very removed from the current idea - and a more abstract thought like, 'what if the psychiatrist was a crocodile'? - very removed and likely to lead to a more original, albeit strange, train of thought, and cartoon.
This process is most recognisable to the people who enjoy cartoons when cartoonists attempt to put a new spin on a familiar cartoon trope,like the Desert Island or Death or the Four Horsemen of the Apocalypse,or Confessionals' I've done one or two of these myself, over the years,and I've seen one or two variations on my 'pants' cartoon for National Lampoon, in a variety of magazines:
Here are a couple of pants-related cartoons from The New Yorker's Cartoonbank. I actually did this cartoon a while before it appeared in the National Lampoon book and I thought it would be a New Yorker cartoon, but they passed and so did The Harvard Business Review and a few others. I liked it though, so I kept punting it. I still like it, I think it might make a good Greetings Card: