The universe is a tested theme in Shakespeare's Folio. Juliet, a Leo, is "star-cross'd" with her lover Romeo in a likely commentary of astrology (I.6). Shakespeare makes a hundred references to simple star-readings in his plays, manipulating their effects on his cast. But in his tragedy of Hamlet, Shakespeare may show his hand in the pressing heliocentric vs. geocentric debate of the universe. "Doubt thou the stars are fire,/ Doubt that the sun doth move" Hamlet writes to his complicated love interest, Ophelia (II.ii.116-117). "Doubt that the sun doth move."
Peter Usher, professor of astronomy and astrophysics at Penn State, proposes that Shakespeare carries his astrological tradition into the tragedy of Hamlet--and multiplies it. Hamlet, he argues, is the allegorical competition between two cosmological designs: the sun-centered Copernicus construct, and the old Earth model retained by Tycho Brahe of Denmark.
In Copernicus' last days, his pupil Georg Joachim pitched the heliocentric scheme at the University of Wittenberg, Germany. The model became the standard of the college, though Tycho Brahe, an active student, retained his staunch Catholic traditions. Brahe, during the construction of his observatory in Oresund Sound, predicted that poets may soon compose songs of praise in his honor. He commissioned portraits sent out in his likeness, posed under a stone arch with the relief of his great grandparents Erik Rosenkrantz and Sophie Gyldenstierne.
Usher argues that Shakespeare knew knowledge of these portraits through a Copernican friend, Thomas Digges. He adds Rosencrantz and Guildenstern to Hamlet as allegorical figures of Tycho and geocentricism; "adders fang'd," feigned friends of Hamlet doomed to die by his hand (III.iv.203). They are all three students from Wittenberg without coincidence. King Claudius, Usher adds, may be an allusion to Claudius Ptolemy, meant to evoke the Greek astronomer's catalogue of constellations and geocentric ideas. Hamlet's Denmark kingdom is named Elsinore, a near homonym of the historical Denmark King's Helsingor castle observatory erected simultaneously with Brahe's own in Oresund Sound. Usher's arguments are convincing.
Here at Elsinore, Hamlet puns he is "too much in the sun," thus associating himself with the sun in its alignment. Following his outburst, the royal couple discourage Hamlet from returning to Wittenberg, Shakespeare's allusion to heliocentric thought. "It is most retrograde to our desire" (I.ii.114). "Retrograde" has its origins in Chaucer's time, the 14th century, when it most nearly meant "backtracking" and "returning to a previous course." Here, in Hamlet, "retrograde" is most certainly a term for "opposition," hinting at the process of retrograde motion in planets. Usher claims there is no doubt in the astronomical pun. "Why should we in our peevish opposition/ Take it to heart?" Claudius asks (I.ii.101). "Fie, 'tis a fault to heaven--" or geocentrists that deem retrograde motion a fault of Nature (I.ii.102). Shakespeare concludes the allusion in Claudius' lines about his Queen in Act IV: "She is so conjunctive to my life and soul,/ That as the star moves not but in his sphere,/ I could not but by her" (IV.vii.16-18).
One of Shakespeare's finest tragedies, Hamlet, Prince of Denmark, if it is as Peter Usher convincingly suggests, an allegory of two competing cosmic worldviews, it may be the most poignant social commentary of Shakespeare's era, and well rivaling the 18th century satirists Swift and Pope whom Shakespeare would never meet. While Peter Usher's scheme for the Hamlet tragedy is mere postulation, it does represent an impressive insight into Shakespeare's possible involvement within the Scientific Revolution and its scientists. Imagine: while in the last year of the 16th century Giorgano Bruno is martyred as a Copernican convert, Shakespeare composes a magnificent, poetic affirmation of heliocentricity--and lives.