Mythology is always elastic and dynamic, and Pan strikes me as more given to shape-shifting than some. A divinity that might have seemed likely to dwell in the humbler precincts of Olympus, half beast in fact, and patron of backward herdsmen, Pan developed into a personification of both principal god and devil. Though an importunate sexually aroused serial rapist, Pan has been as well the occasion for a vision of Ultimate Reality. These observations stubbornly would not cohere, so I present them as a series of notes.
Pan’s name was derived from “pasturer,” and the god governed the opposite pole of Zeus’ royal court: those semi-wild heights, unowned by any so free to all, where sheep or goats could find fodder. His pipes resemble those used by Greek shepherds from the third millennium BCE. Like the land that could sustain domestic animals, he was a blessing, with the epithet of “luck-bringer,” but at times, both in the mountains and on the battlefield, he could bring on panicked terror as well. He personifies sexual desire, but sometimes pursues females with selfish passion, according to the stories of Echo and Pitys. His frightening aspect could be beneficent as in Pheidippides’ report of his aiding the Greeks by causing panic among the Persians is told by Herodotus,  but it gave even the Arcadians pause. His intimate appeal to the individual is perhaps implied in the fact that the archaeological remains reveal a great many dedications but few dedicated temples. Offerings to Pan were often left in the wilderness.
Philologists tell us that the folk etymology pan=all (accepted in late antiquity) is inaccurate, yet it has a broad unfocused appropriateness for a deity of generation, and Pan has often been used to represent paganism as a whole. Human awe at the ability of life to generate new plant and animal life led to exaggeration of his sexual characteristics and his frequent ithyphallic representation in art.
These characteristics are attested by the poets. Pindar refers to Pan’s archaic identity as an attendant of the Great Mother, a role consistent with his association with fertility.  Stories of Pan’s human mother (said to be Penelope in her wild older years)  doubtless encouraged people to feel closer to Pan than to the full Olympians. In Euripedes’ Helena Pan’s capacity for exciting terror is the focus, here with reference to the rape of a naiad.  Pan stands at the very opening of Theocritus’ Idylls. In an atmosphere both rural and erotic, Thyrsis praises the Goatherd’s music as second only to Pan’s, associating both with ample meat to complete the festive note, yet he also refers to the threat of Pan’s anger when disturbed at his siesta. One delights in food and in love only if one also is liable to the pains of a lack of either. The same interdependent complex is implied in Theocritus’ VIIth Idyll in which the poet appeals to Pan for success in love, but incidentally refers to the custom of flagellating Pan with onions when food proves insufficient.
Pan in Plato
In his Cratylus Plato echoes Hesiod’s muses who warned humans (whom they called “mere bellies”) that, while they may deliver the truth, they also “know how to speak many false things as though they were true.”  Socrates tells Hermogenes that Pan is “double-formed” because “speech signifies all things (pan), and is always turning them round and round, and has two forms, true and false.”  This striking anticipation of modern concepts of the inherent limitation of language occurs in a dialogue which has, quite appropriately, itself been viewed with uncertainty by readers who cannot tell what is meant to be Socrates’ position on the issue of whether the signifier is linked to the signified or is wholly arbitrary. Socrates changes his mind, or at least the direction of his argument in mid-dialogue. Further, the lengthy presentation of fanciful etymologies has been considered satirical by some and serious by others.
Socrates does trace a pattern in these weird imaginative speculations on the origins of words: the repeated mention of flux. To him this signifies a fundamental doubt at the basis of the world-view of the “name-givers” which has led them to insert hints of instability into the verbal code. “Namemakers believed everything to be in flux. Suppose it should prove that although those who gave the names gave them in the belief that all things are in motion and flux—I myself think they did have that belief— still in reality that is not the case, and the namegivers themselves, having fallen into a kind of vortex, are whirled about, dragging us along with them.” 
In the end Socrates is not so distant from Huang Po who directed his listeners to gaze to the Mind behind phenomena, reinforcing rather than negating everyday experience in the process. Lacking the nonverbal intuition by which both Greek and the Chinese thinkers apprehended truth, Cratylus can only play the part of the absolute skeptic.
In the Phaedrus Pan was Socrates’ god of choice to whom he offers a most philosophic prayer, directing his words also, in a pleasantly ecumenical gesture, to “whatever gods may be present.” Socrates asks for inner perfection and for only such possessions as a reasonable man can handle, noting that the only true wealth is wisdom. 
Pan and Christ
Herodotus suggests that Pan is, along with Dionysus and Heracles, a younger god  yet he adds that, among the Egyptians (who, he assures his readers, kept excellent records) he is considered to be very ancient. The archaic character of his role as producing fertility, both plant and animal, in wild regions, might seem to support the latter judgment, at least as far as a local cult in Arcadia is concerned. He shares with Christ, Dionysus, and Heracles the non-Olympian characteristic of a mixed human/divine parentage and a career including the human experience of death.
Plutarch  tells the story of Thamus, the Egyptian ship’s pilot, who learned in a divine vision of the death of the god, news which eventually reached Tiberius who launched an investigation. As the date of this incident happened to coincide, roughly, at least, with the crucifixion of Jesus Christ, the story has been used to signify the end of paganism and the triumph of the Christian deity with his resurrection. For Eusebius it added to what he saw as considerable evidence that the pre-Christian gods has departed to make way for his god.  By the time of the Renaissance, the death of Pan had come to signify not the departure of the Greek deities, but Christ’s redemptive death itself. Orthodox authors such as Rabelais (for whom, of course, Panurge and Pantagruel are heroes) and Guillaume Bigot identified the two gods and treated Pan’s death as a figurative way of speaking of Christ’s own.  Rabelais says, “For my part, I understand it of that great Saviour of the faithful who was shamefully put to death at Jerusalem by the envy and wickedness of the doctors, priests, and monks of the Mosaic law. And methinks my interpretation is not improper; for he may lawfully be said in the Greek tongue to be Pan, since he is our all. For all that we are, all that we live, all that we have, all that we hope, is him, by him, from him, and in him. He is the good Pan, the great shepherd, who, as the loving shepherd Corydon affirms, hath not only a tender love and affection for his sheep, but also for their shepherds.” 
This reading of Pan as a symbol of Christ reached England as well. In the month of “Maye” in Spenser’s Shepheardes Calendar Pan is simply a code-word for Jesus: “When great Pan Account of Shepherds shall ask.” (54) Milton follows in his “On the Morning of Christ’s Nativity” in which the shepherds find that “the mighty Pan/ Was kindly com to live with them below.” 
Pan and the Romantics
Wordsworth and Byron both used Pan as the representative of a paganism which for them meant primarily aesthetic values. When Byron recounts the story from Plutarch of Pan’s reported death in “Aristomenes,” Pan represents paganism as a whole. The loss of the pre-Christian world-view seems to the poet an aesthetic loss.
How much died with him! false or true—the dream
Was beautiful which peopled every stream
With more than finny tenants, and adorned
The woods and waters with coy nymphs that scorned
Pursuing Deities, or in the embrace
Of gods brought forth the high heroic race
For Wordsworth this meant a gentle soothing landscape picturesqueness as in the sonnet “Composed By the Side of Grasmere Lake” in which “Great Pan” “low-whispers” “tranquility is here.” One recalls that in “The World Is Too Much With Us” the poet wishes that, as a pagan, he might be made “less forlorn” by such entertainments as the “sight of Proteus rising from the sea;/ Or hear old Triton blow his wreathèd horn.” This is religion reduced to the amusement of sight-seeing.
In Shelley’s “Hymn to Pan” the god is not, as in Wordsworth and Byron, the representative of a picturesque and charming mythology, but is instead a model for the very human experience of delusive desire.
“I pursu'd a maiden and clasp'd a reed.
Gods and men, we are all deluded thus!
It breaks in our bosom and then we bleed.
All wept, as I think both ye now would,
If envy or age had not frozen your blood,
At the sorrow of my sweet pipings.”
(Mary Shelley for her part wrote a play Midas -- which I have yet to read -- with two lyrics by Percy to open with the music contest between Apollo and Pan.)
Keats is far profound, original, and provocative in his use of Pan as a sort of objective correlative of negative capability. In Endymion  Pan is first described as a Romantic nature spirit ruling “desolate places, where dank moisture breeds/ The pipy hemlock to strange overgrowth.” to whom “yellow-girted bees” offer their honey. He is associated with the sort of magic likely among farmers “Breather round our farms,/ To keep off mildews, and all weather harms,” yet for Keats he is above all mysterious. The “Strange ministrant of undescribed sounds,” and “Dread opener of the mysterious doors/ Leading to universal knowledge.” At the hymn’s conclusion this has become a virtual mystic via negativa:
be still the leaven,
That spreading in this dull and clodded earth
Gives it a touch ethereal—a new// birth:
Be still a symbol of immensity;
A firmament reflected in a sea;
An element filling the space between;
Pan and Neo-Paganism
The earlier use of Pan to represent all pagan deities persisted into the nineteenth century, though the associated values altered. Elizabeth Barrett Browning in the extended exclamations of “The Dead Pan” maintains a conventional preference for the new god, “one in Sion/ Hung for love’s sake on a cross,” but her successors did not prove always so orthodox. To some post-Romantic poets, this god’s resemblance to the Christian devil in his horns and cloven hooves proved more an attraction than an impediment to his renewed worship as an icon of eroticism, forbidden pleasure in general, and the unconscious.
This use of Pan as a mask to protest appears in Baudelaire. In “La Muse Malade” Pan is recognized as god of poetry together with Apollo, but the recognition is largely nostalgic. This belated author’s muse is characterized by “folie et l'horreur, froides et taciturnes.” In “L'École païenne” Pan is identified directly with revolution and his return with the end of the tyrannical reign of Christianity. Baudelaire details this view in The Painter of Modern Life  he maintains “The birthplace of Painting is the Temple. Its roots are in religion. The modern temple and the modern Religion are the Revolution. Thus let us create the Temple of the Revolution and the Painting of the Revolution . . . Pan must kill god. Pan is the people.”
Varieties of this counter-cultural Pan are discernable in paintings by Burne-Jones such as Psyche and Pan  in which a dubious looking naked female stands well below an amorous Pan whose coiffure is positively architectural. The excitable Swinburne identifies Pan with élan vital in “A Nympholept;” the even more irregular Aleister Crowley made Pan a major symbol of his Thelemic mysticism and sang wildly of his wish to “Thrill with lissome lust of the light,” 
Most readers of poetry can call to mind e. e. cummings’ balloon man, at first called “little” and “lame,” then “queer” and “old,” until the cat is let out of the bag and he is said to be “goat-footed.” 
1. Histories, (I, 105).
2. Pythian iii. 77, fr. 6. 1.
3. Apollodorus Epitome (7.38) says Odysseus’ Penelope conceived Pan after she was ousted for infidelity by the hero.
5. Theogony, ll. 26-28.
9. Histories, II. 145.
10. Moralia, “The Obsolescence of Oracles,” 419.
11. Eusebius of Caesaria, Praeparatio Evangelica, Ch. XVII.
12. By the beginning of the 18th century this trend had become sufficiently pronounced to be ridiculed. Thus Fontenelle comments, “Ce grand Pan qui meurt sous Tibere, aussi bien que Jesus-Christ, est le Maistre des Demons, dont l'Empire est ruine par cette mort d'un Dieu si salutaire a l'Univers; ou si cette explication ne vous plaist pas, car enfin on peut sans impieté donner des sens contraires a une mesme chose, quoy qu'elle regarde la Religion; ce grand Pan est Jesus-Christ luy-mesme, dont la mort cause une douleur et une consternation generale parmy leg Demons, qui ne peuvent plus exercer leur tirannie sur les hommes. C'est ainsi qu'on a trouve moyen de donner a ce grand Pan deux faces bien differentes.” This passage and many more are included in O. Weinreich’s article “Zum Tode des Grossen Pan,” published in ARW 13 (1910) pp. 467-73).
13. Book. IV, Ch. 24. This is Urquhart’s version.
14. ll. 89-90.
15. The passages cited all occur in the episode in I, 232-306.
16. In Chapter 10, “Philosophic Art.”
17. See also “The Garden of Pan” in which a buff lad plays his pipes for a pair of lovers while gazing directly at the viewer.
18. “Hymn to Pan.”
19. “in Just-“