Though Blake is often considered part of the Romantic movement, his work is unique and does not wholly fit in with the trends of his time. Much of his poetry predates Wordsworth and Coleridge but cannot even be classified as belonging to that transitional period in English poetry between the classical (or neo-classical) and Romantic eras. Still, "The Tyger," as a representative poem from his Songs of Experience, does express themes not inconsistent with the late eighteenth-century and early nineteenth-century Zeitgeist.
Blake often deals with dichotomies of human thought and feeling. He also tends at times to use an inverted vocabulary in which words take on the opposite features of their conventional meaning. That which is characterized in seemingly negative terms is often a positive symbol for Blake. In his life as well as his work, he was an iconoclast and a rebel, and this part of his character marks him as typical of the Romantics. The tiger/tyger of his poem stands for that defiant, subversive side of human nature that other poets who came a few decades later, such as Byron and Shelley, reveled in. It also symbolizes the rejection of religious norms which typifies the Romantics:
When the stars threw down their spears,
And watered heaven with their tears,
Did he smile, his work to see?
Did he who made the Lamb make thee?
The God who created the Tyger is not the God of tradition or one of peace. The animal is an emblem of ambiguity, existing in some new world "beyond good and evil," to use the terminology of Nietzsche from nearly a century later. Blake celebrates this violent spirit which defies convention and creates its own set of rules. In asking what immortal hand or eye could frame the "symmetry" of the Tyger he is almost stating that the beast is beyond the power of the Creator to control it. Even the unconventional spelling is emblematic of this defiance of norms, this uncontrolled being that creates its own values and jettisons the past.
Is this relevant today? For decades we have lived in a world of constant flux, in which societal norms have been reevaluated, rejected and altered over and over again. In some ways Blake, in his standing as a sui generis artist (and his art encompasses not just writing but painting as well), would fit into our time better than would his contemporaries, the "true" Romantics. The Tyger's "forests of the night" are a realm of ambiguous meaning, dangerous but alluring in their darkness. In our time, when so many of the older values and belief systems have been questioned and overturned, Blake's Tyger could very well be symbolic of the new human spirit of our age.