Love, laughter, art, and the difficult struggle to break through to a fecundating tenderness and creativity may be described as Durrell's primary themes as well as his chief social concerns. Certainly the work is fundamentally a bildungsroman, and its basic thrust is the growth and education of its central character and narrator, Darley. This central quest — what Darley learns — carries him through, as Durrell writes, "the politics of love, the intrigue of desire, good and evil, virtue and caprice, love and murder," all of which move "obscurely in the dark corners" of Alexandria, move "like a great congress of eels in the slime of plot and counterplot." Slowly, with many visions and revisions, Darley learns love, and achieves maturity as man and artist.

Put more simply, the primary theme has to do with the quest to break through isolation and loneliness, to realize fullness of life and art through complete commitment to the creative process. This process, however straightforward as it may sound when stated boldly, is extraordinarily complex as Durrell works it out in the tetralogy, and it is everywhere dependent upon the structural and thematic force of the "relativity proposition." For Durrell, the relativity patterns dictated by Einsteinian Space-Time considerations are reinforced and underlined by the process of psychoanalysis. Thus, in brief, Truth and Identity are discoverable only in relationships.

Another major theme in The Alexandria Quartet, and throughout the Durrell canon, may be summed up in the phrase: "character is a function of landscape." Beginning with The Black Book, where the protagonist is in flight from the "English Death," most Durrell characters flee the dark, drizzling, life-denying Protestantism of a gray, abstract, sterile world, seeking a Mediterranean world of warmth, fertility and affirmation, a world where the deus loci, the numinous spirit of place reigns. Under the ancient sun of the Mediterranean world, under the benediction history, characters may discover the "heraldic" universe. As Darley says: "We are the children of our landscape. It dictates behaviour and even thought in the measure in which we are responsive to it."