Magic
Magic is the primary spiritual form in this collection, replacing religion as a place to turn in a time of distress. Yeats was brought up in a Protestant family, but turned to theosophy when he became an intellectual. Theosophy, a set of beliefs that declares that all religions hold some measure of truth, tends toward the fantastical in practice. Yeats attended séances and exercised what he called “automatic writing”: writing funneled through a poet. These magical trappings are evident in many poems in The Tower, including the speaker’s ability to call on the “sages” in “Sailing to Byzantium” or the ghosts in “All Souls’ Night.”
Magic provides one possible solution to the crisis that the poet puzzles over throughout this collection: aging. As he points out in “The Fool by the Roadside,” only a fool thinks that life can be made to go from the end point to the beginning, instead of the other way around. But the poet casts himself as this fool, and it seems to be his earnest wish to reverse the life cycle. When he is attended upon by the sages in “Sailing to Byzantium,” a reversal, a rebirth, does seem possible. The poet will be reborn through healing fire, like the phoenix.
Fishing
The activity of fishing appears throughout this collection as a metaphor for youth, life, and health. Yeats uses it to counteract the images of aging. The most common, variations on the image of “tattered rags on a stick,” is the inverse of fishing. Instead of controlling the rod, a symbol of virility, the aged man is himself trapped, no longer the fisher but the fished.
Fishing holds not only a symbolic but also a historical significance for Yeats, who used to fish during his childhood in the hills of County Sligo. The fish leaping in the water is a common trope for fertility, and Yeats’ special mention of salmon leaping upstream is biologically correct (there are many salmon in Irish rivers) and also a possible comment on the Irishman’s stubborn and heroic nature. In “The Tower,” Yeats leaves the fishermen his pride in his “will.” Although he is no longer one of the young, he seems to identify with and admire them.
Destruction
In keeping with the collection’s more general theme of death, Yeats supplements the images of decay with those of active destruction. In addition to nature and time playing an active part in the destruction of the human body, other humans may also choose to destroy one another. In many poems, the speaker seems afraid of the former and horrified by the later.
Part of the horror of destruction is an intrinsic belief in the goodness of beauty and the human body. In “Nineteen Hundred Nineteen,” Yeats describes the destruction of an ancient statue and the mob’s complete disregard for its beauty or historical significance. Of course the more salient destruction that the IRA and the Black and Tans (they, too, in many senses could be considered a mob) carried out was killings. In mourning the destruction of a beautiful statue, the poet creates a symbol for the slain human and affirms its beauty and significance. Images of destruction, whether they be killings as in “Meditations in a Time of Civil War” or less direct references, appear most frequently in the more political poems in this collection.
The Moon
The moon appears so often in this collection that its significance must be weighed. It is the countersymbol to the destruction that plagues much of the rest of the collection; it is the female force. But although it is a peaceful symbol, the moon also has an edge of danger.
Yeats often compares the moon to a beautiful woman, or draws parallels with Maude Gonne, the woman who refused to love him back. Yeats plays on the word "lunacy" to support the ancient myth that madness and the moon were tied together. This, together with the moon's feminine associations, implies that women, too may drive men mad. This is in keeping with the theme of unrequited lust.
Unrequited Lust
Many poets write of unrequited love, but Yeats, in this collection, confronts unrequited lust. Part of the experience of aging seems to be the loss of physical attractiveness. In “A Man Young and Old,” the speaker mourns, “My arms are like the twisted thorns/ And yet there beauty lay.” The speaker has been in and out of love, but desire for young women still remains. This is part of the contradiction of a young spirit trapped in an old man’s body.
Yeats uses the word “lecher” to describe a person in this situation; it is clear that although he mentions this sort of lust in many of the poems he is aware of the moral aspect of the unequal lust. In “Owen Aherne and his dancers” it seems there is a possibility a young girl might “mistake her childish gratitude for love,” but the speaker resolves to “let her choose a young man and all for his wild sake.” His strongly expressed desire, not fully but half returned, makes this ending seem generous and self-denying. This resolution does not, however, prevent this sort of desire from reoccurring in other poems.
Immortality and Classicism
A poet so preoccupied with the issue of aging is naturally also preoccupied by the issue of immortality. Critics have explained the shift away from Irish and toward Classical mythology, once again, with Yeats' friendship with Pound and his interest in the modernist literary movement. Putting this aside, however, Irish mythology is much more vague about immortality than Greek or Latin: in which the gods, and some of their favored mortals, live forever. This may explain the hopeful color that references to Juno and Athena add to some of these poems, and the explicitly classical-themed "Oedipus at Colonus."
Danger
Danger is ever-present in this collection, whether it be through age, brokenheartedness, or violence. Much of Yeats' description of danger has to do with a heightened time scheme: all men age, but the speaker in "Youth and Age" seems worried about imminent death. All men die, but the speaker in "Meditations in a Time of Civil War" is likely to face sudden death at the hands of intruders.
Danger, characterized by a heightened urgency, creates uncertainty, and that is a dominant mood in The Tower. Continuity is represented in this collection by art, especially sculpture, which is a stand-in for culture more generally. Once this is destroyed by the mob, there is no telling what or whom the mob will destroy next. This mood is not confined to Yeats alone, but is visible in much of the literature written directly after WWI.