There's even a web site for the syndrome.
I really don't like being grumpy about human psychology, but it occurs to me first that some of these young academics are (merely) feeling panic about not having as much knowledge about their fields of expertise as they feel they need to have. In other words, they are imposters, in a sense. Or: they're in a profession where one doesn't really know enough until one has been thinking, teaching, writing and studying for a decade or more. Or: one will never know enough. (And yet they must publish, so almost by definition what they write will be based on significantly incomplete knowledge. It all makes sense. In fact, too much sense.)
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Once I met Bill Ringler, then more than 80 years old, I always made a dash to Bill's table. Bill was the world's foremost bibliographer-scholar of 16th-century English lyrics. By the time I met him he knew most of them by heart. Really. He had not been a hugely productive scholar--in, I mean, terms of the number of books and articles he'd published. But everyone knew that he knew more about his subject than anyone else. People used to come to the Huntington to be near Bill--never mind the rare books. He was a rare book.
He had taught at the University of Chicago for decades, and now he "retired to the Huntington." Lived in Pasadena or somewhere and walked to the library every day and studied. Preparing himself to compile the once-in-a-generation tome.
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I'm not of course recommending that any of these nervous young academics wait decades before feeling they know their subject matter well enough to feel they can write definitively about it. I'm just reacting to the sad but also obvious or truistic news of the imposter complex. Bill Ringler had one, big time, but it put him at peace, and made him want to get up in the morning at an age when many folks, having been driven by nervousness all their professional lives, now drool and putter around the roses.
Bill puttered around the roses, as did I in those blissful weeks in Research Heaven, but only for that one enforced hour each day. Then: back to the work.