According to Henslowe’s diary Marlowe’s »The Jew of Malta« has been staged February 1592. It was registered 1594 in Stationers’ Hall, but printed only 40 years later (1633). Shakespeare’s »A booke of the Marchaunt of Venyce, or otherwise called the Jewe of Venyse« was registred July 1598 in Stationers Hall, (mentioned already February 1598 by F. Meres) and printed as quarto 1600 (»The most excellent History of the Merchant of Venice. With the extreme cruelty of Shylock the Jew towards the sayd Merchant….«).
There can be no doubt that in the „Merchant of Venice“ Shakespeare must have „extensively plagiarized„ from Marlowe‘s „Jew of Malta“.
Is this conceivable? How should we imagine William Shakespeare as a human beeing? Is there a more plausible theory?