"No one can be aware of everything that has been previously published relevant to one’s interests "

In an email to Inside Higher Ed concerning the controversy surrounding Terrence Deacon’s book, Incomplete Nature: How Mind Emerged from Matter, Steven Pinker, a professor of psychology at Harvard University, writes:

“Every year thousands of academic books are published, and no one can be aware of everything that has been previously published relevant to one’s interests. Also, many ideas, when stated at a high level of generality, will inevitably occur to several people independently, and usually in different forms. The devil is in the details, and in this case it is clear that Deacon has worked out a theory that in no way is derivative of others’ approaches.”

See Publicizing (Alleged) Plagiarism by Alexandra Tilsley

Harvard itself has been dogged by plagiarism problems, including those surrounding Laurence Tribe of the Law School.

And of course there is the Harvard Business Review. At page 68 in the April 2004 issue of HBR, one has in the article that became the basis for Hardball:

Plagiarize with pride.

Softball competitors like to think that their bright ideas are sacred. But hardball players know better. They're willing to steal any good idea they see --as long as it isn't nailed down by a robust patent -- and use it for themselves. Ray Kroc didn't invent McDonald's; he took the idea from brothers Dick and Maurice McDonald when he bought their small chain of burger joints. Home Depot founders Arthur Blank and Bernie Marcus didn't invent the first warehouse-outlet hardware chain; they got the "big box" concept from their earlier employer, Handy Dan Home Improvement.