It’s not the precise accuracy of any particular theory — for example the suggestion that Shylock was inspired by the Queen’s Portuguese-Jewish physician — that Greenblatt makes so persuasive. Rather, he convinces you that he has sunk so deeply into Shakespeare’s time, mind and imagination that his guesses must be better than anyone else’s. As a founder of New Historicism, a once controversial, now widely accepted school of literary criticism holding that writers works are profoundly shaped by the physical, cultural and political worlds they live in, Greenblatt has plenty of experience in this department.

Slavering bardolatry is always a peril in such projects, and no doubt Greenblatt hung a photo of Harold Bloom over his desk while he worked: Exhibit A of Where Not to Go. By contrast, his own account of Shakespeare the man remains as grounded as the playwright’s vision, described by Greenblatt as “bound to the familiar and the intimate,” so that it “never soared altogether above the quotidian, never entered the august halls of the metaphysical and shut the door on the everyday.” Stars wiped from his eyes, Greenblatt gives us a Shakespeare who can’t fail to stir — he’s still Shakespeare, after all — but also a writer who presents some unsettling questions about the nature of creative genius.

“Shakespeare in Love,” on the other hand, offers an easy, pleasing dream about great artists. It tells us they are just like the rest of us, only more so. Because Shakespeare’s words have the power to flood us with overwhelming sensations — both the recollection of our own strongest feelings and those transports we only experience in the presence of made beauty — people, perhaps naturally, want him to have been a grand and passionate man. According to the film, the only force capable of propelling Shakespeare — or anyone, for that matter — into the ranks of the immortals is romantic love, that Holy Grail of popular culture, and “Romeo and Juliet,” the play that results from his dalliance with Paltrow’s stagestruck noblewoman, becomes his entrée to greatness.

Although Greenblatt writes with tactful kindness about “Shakespeare in Love” (he got the idea for “Will in the World” during conversations with the movie’s screenwriter, Marc Norman), he surely can’t think much of this premise. Firstly, it pretends that romantic love was Shakespeare’s prime subject, which is patently untrue, however closely it hews to the image of poetry held by people who never read it. Second, it makes Shakespeare himself out to be a romantic, and Greenblatt devotes two chapters of “Will in the World” to arguing just the opposite.

Shakespeare wrote about love because he wrote about all of life, and some of his works — the sonnets, “Romeo and Juliet,” “Antony and Cleopatra” — put romantic love at their center. But even in these, the world seeps in, and the world in its fascinating particulars is the enemy of the all-consuming love that swallows Romeo and Juliet. Even the sonnets, supposedly devoted to praise of the beloved, get distracted by their own eloquence and slip into boasting about the triumph of art. “Shall I compare thee to a summer’s day?” begins Sonnet 18 (written, according to “Shakespeare in Love,” to Paltrow’s crossdressing heroine, although in real life to a young man), but it ends by proclaiming that while fleshly beauty fades, “So long as men can breathe or eyes can see,/So long lives this, and this gives life to thee.”

“Shakespeare in Love” briskly dismisses the inconvenient fact that its hero has a wife and three children back in his hometown of Stratford by writing off the marriage as sexless. Greenblatt also subscribes to the opinion that Shakespeare’s marriage to Anne Hathaway was unsatisfying. Perhaps the two were mismatched, but Greenblatt, after contemplating the traces in Shakespeare’s work of other affairs, suspects that “no single person could ever have satisfied Shakespeare’s longings or made him happy.” The playwright’s imagination, after all, was anything but “single;” it had the “signature characteristic” of an “astonishing capacity to be everywhere and nowhere, to assume all positions and slip free of all constraints.”

In an earlier chapter Greenblatt writes of how in Shakespeare’s work his “fascination with the lives of aristocrats and monarchs” serenely coexisted with his affection for the country life of his childhood. He did not feel compelled to choose, and Greenblatt proposes that “he simply loved the world too much to give any of it up.” Romeo and Juliet die to preserve their love, and as Greenblatt points out, the two most developed portraits of marital intimacy in the plays are problematic to say the least: Gertrude and Claudius in “Hamlet” and Lord and Lady Macbeth, marriages that are homicidal in one way or another. If romantic love must murder the world in order to replace it with the couple, Shakespeare wasn’t interested.

The Marlowe partisans have greater pretensions to seriousness than Hollywood, but they share its desire to fabricate a flashier vessel for Shakespeare’s gifts. Although both men came from modest families (Shakespeare’s father was a glove-maker and Marlowe’s a cobbler), Marlowe had more formal education. He belonged to a group of writers called the “university wits,” who had in common “impressive learning, literary ambition, duplicity, violence, and rootlessness.” One of them, Thomas Nashe, the Dale Peck of his day, made his reputation by penning “a harsh review of recent literary efforts — the cruel judgements of a brash young man,” but the university wits wielded more than metaphorical hatchets. Like his friends, Marlowe, who died after being stabbed in the eye during a tavern brawl that many suspect was a hired killing, freely dabbled in crime, espionage and declarations of atheism, a particularly dangerous practice at the time.

Marlowe was also a writer of immense talent, and ever so much more dashing than the prudent, frugal Shakespeare. Admittedly, the painted portrait of Marlowe included with the illustrations of “Will in the World” cannot be authenticated. But the bold, amused and supremely confident Elizabethan it depicts personifies everything the Marlovians find appealing in their man when compared to the more tentative, even anxious face we see in portraits of Shakespeare. Who wouldn’t consider the glamorous, shadowy, reckless Marlowe as better casting for the creator of Iago, Lady Macbeth and Mercutio?

Anyone who’s actually read the two men’s plays is who. Greenblatt doesn’t deign to mention Marlovian conspiracy theory (or any other such claims involving aristocrats and intellectuals of the time) in “Will in the World,” but he does compare Marlowe’s work with Shakespeare’s, brilliantly and at length, to demonstrate the fundamentally different sensibilities behind each.

Marlowe was a kind of proto-Nietzschean fascinated by characters who overreached, regardless of the consequences. His “Tamburlaine” is, as Greenblatt puts it, an “incantatory celebration of the will to power.” He might have invented Iago, but the likes of Falstaff and Hamlet are surely beyond him. By way of example, Greenblatt details how both men wrote plays with Jewish villains, stock characters in a country that was virtually devoid of real Jews. But, as Greenblatt points out, Marlowe’s Jew was thoroughly and gleefully wicked, while Shakespeare’s is shot through with veins of dignity and pathos, a display of the “strange, irrepressible imaginative generosity” that distinguishes the Stratford-born playwright from his rival.

But if the real Shakespeare wasn’t the dreamy, love-struck poet of “Shakespeare in Love” and wasn’t imbued with the (equally romantic if more sophisticated) bravura of Marlowe, then who was he? According to Greenblatt, Shakespeare was “a prosperous, self-made man,” who dabbled in but ultimately rejected the “chaotic, disorderly life” of London’s literary scene. Having been raised among clandestine Catholics, people who risked everything for their outlawed faith, he distrusted true believers and outright rebels, and developed what Greenblatt delicately terms “a complex attitude toward authority, at once sly, genially submissive, and subtly challenging.” He may not have loved his wife, but he certainly never loved anyone else enough to abandon her. Due to his “lifelong interest in property investments” (most of the records of Shakespeare’s life are real estate documents) he retired at the top of his game to a quiet, comfortable life as a country burgher.

As Greenblatt writes, a look at Shakespeare’s life makes the playwright seem a “drabber, duller person” than one might hope. Worse, there’s more than a hint of parsimony. In one of the book’s most fascinating chapters, Greenblatt finds a possible model for the portly rascal Falstaff in the writer Robert Greene. Greene is now most famous for a deathbed rant in which he denounced an “upstart Crow, beautified with our feathers,” obviously Shakespeare, who has infiltrated the circle of the university wits and passed himself off as their successor. Greenblatt speculates that Shakespeare earned Greene’s wrath when he “turned down some [probably monetary] request from the indigent, desperate scoundrel.” Instead, Shakespeare “conferred upon Greene an incalculable gift, the gift of transforming him into Falstaff,” a legendary character.

Audiences have always been somewhat chilled by the climactic banishment of Falstaff by Prince Hal — “I know thee not, old man” — at the end of “Henry IV, Part II.” As commoners, as audience members, we can afford to cherish Falstaff, but Hal has become king, in effect another person, and there is now no place in his life for his old drinking buddy. Hal’s rejection parallels Shakespeare’s, writes Greenblatt; it was “what he had to do in order to survive.” But if Hal repudiates Falstaff, the play immortalizes him. Shakespeare may have refused to give Greene money, but he “also performed a miraculous act of imaginative generosity, utterly unsentimental and, if the truth be told, not entirely human.” (Greene, like Falstaff, would surely have preferred, and squandered, the cash.)

If Shakespeare identified with Hal, whose destiny demands a certain cold-bloodedness, then perhaps he would have agreed with another author named Greene, Graham, who said that a chip of ice lies in the heart of every writer. To celebrate and identify with all of creation, to effortlessly submerge yourself in a clownish bumpkin like Bottom, a mad old man like Lear, a brave girl like Rosalind, or, as Greenblatt elegantly demonstrates with passages from Shakespeare’s early poem, “Venus and Adonis,” a hare, a horse and the goddess of love — this uncanny mercurial aptitude suggests an absence of the usual preferences and attachments that is, yes, generous, but again, not entirely human.

Yet why should an inhuman generosity be surprising in a man whose “work is so astonishing, so luminous, that it seems to have come from a god and not a mortal, let alone a mortal of provincial origins and modest education”? What Greenblatt’s “Will in the World” pushes us toward is the realization that enormous talent is always freakish, always defies explanation and may be the last shred the secular world retains of the divine. It is the fabulous cuckoo’s egg in the nest of ordinary life. There is simply no reason why a fairly conventional Elizabethan Englishman should have become the greatest imaginative artist the language and perhaps the world has ever known. We can find shards of Shakespeare’s life and society in his work, but we can’t find intimations of the work in his life or ever nail down how Shakespeare became Shakespeare if by “became Shakespeare” we mean “came to be able to write those plays.”

We’re like Lear, finally reunited with Cordelia and assuming that she does not love him. Unlike her sisters, he says, she has “some cause” to do him wrong. Cordelia answers, “No cause, no cause.” Her love for her father, which is her great talent and a decidedly more natural one than Shakespeare’s, is not the sort of thing that has a cause. It just is.