Great works: The Dance of Albion (circa 1795), William Blake

British Museum, London

This is a hypothetical image for a hypothetical day. It's an affirmative vision for a moment that's very unlikely to be now. It was chosen in advance, of course. But whatever results are emerging this morning, William Blake's The Dance of Albion can only feel like a cruel irony or a bitter protest or an impossibly remote ideal. Even in its own day, it was highly optimistic.

Albion is England, a personification of this island. In this picture – also known as Albion Rose or Glad Day – he symbolises England's political awakening and liberty. A naked man stands on a rock in a sunrise, rising above the material world, welcoming the dawn. This elemental scene was coined at a time of revolution and repression, and Blake added captions to focus his meanings. Pictorially, there's nothing to set it in any specific age or place or politics.

All the same, Albion represents a uniquely utopian figure. His body itself speaks an abstract but articulate language. This nude is delivered from all bondage and all untruth. It is beyond conflict, beyond struggle and inner struggle, wholly realised. And yet this figure isn't stuck in final utopian lifelessness, as you might suspect. He holds an interplay between static pattern and dynamic tension.

Stasis first. The figure is a centrifuge. Its energy is fully released. It's the polar opposite to another static form, often used by Blake – a human body self-imprisoned, totally compacted into a ball or a block, its power pent up and contained. Albion goes all the other way. His body is flung outward. His limbs unbend and reach out as far as they can, and each limb is free of others. He is absolute liberation.

The figure is innocent. It has no sophisticated classical complexity, no graceful twisting of torso and stance. The naked body lies on a single plane, and it faces full frontal. Its arms are not raised in victory either, but level and opened to the world. The figure is at the point of maximal unfolding. There is no potential in this pose, no compression, implying something further. This stance is fully actualised. It has arrived, now!

This is the figure's utopian aspect: its uttermost unfolding, its extreme openness and unboundedness. And this simple pose is what gives it an archetypal power. The body is identified with a bold clear shape. But if that was all there was to it, this figure would only manifest a perfect and inert simplicity. You'd have a version of this image where the body was mapped onto a regular diagram, like a human starfish. It would lack any feeling of desire and spontaneity.

Albion eludes this strict diagram. His figure has dynamic elements. For example, his pose is centrifugal, but not altogether. You see strain in his gestures. His hands don't stretch right out, they are flexed right back. They indicate that Albion still wants more, more. He's trying to embrace the world, more than he can embrace – or trying to display his body, more than he can display. His reach exceeds his grasp.

Meanwhile, his legs break a stable symmetry. One stands upright and supporting on the rock; the other is on the wing, lightly and gracefully touching down. The body's weight is uneven. The foot begins to lift. The head is slightly turned. Action enters the figure. The Dance of Albion is in the middle of a dance step, and its level arms are keeping its balance. It might be on the point of a spin. So the utopian figure is saved from being fixed and rigid. It is still aspiring and still moving.

And then a pattern returns, and at another level. This image has a ruling design, a radiant structure, which incorporates the whole figure and all its limbs and everything. Arms and legs emerge like the spokes of a wheel, roughly centred on the diaphragm, but it's not merely a matter of the anatomy. The crucial device here, never used by Blake elsewhere (or by anyone else) so explicitly and so strongly, is the equation between the body and its background.

The outflung stance of Albion is picked up and drawn out by the radiating beams around him – his own shining aura, perhaps, or an entire sun-bursting sky, which is also a multi-coloured flame and a flowering and a butterfly wing. Likewise, the glowing substance of Albion's flesh is on the point of physically merging with this radiance, so that the body could be materialising out of light or dematerialising into it, and the energy of the body is at one with pure energy. His head explodes into a flare.

Albion is in glory. England is in union with the universe. All worldly politics is dazzled. Who could ever imagine this glad day on any morning, or dare to frame this image on any public poster? It could only be propaganda for a party of apocalypse.

About the artist

William Blake (1757-1827): painter, printmaker, visionary, myth-maker, religious and political revolutionary, aphorist, poet. But for all his multiple accomplishments you never find anyone calling him a "Renaissance man". He's not respectable enough for that title. The shadow of eccentricity still falls on his greatness. His visual work, for example, is an unresolvable blend of staggering originality and limitation. He trained and worked as an engraver and illustrator. He weirdly mixed the influences of Michelangelo and Gothic art - and mixes up text and image even more inextricably than a medieval manuscript. There's a sense in which he can't draw. His colour schemes are unheard of. His images are stuck in a sealed-off, home-made system. His human figures are always spiritual symbols – and in the process, his art becomes a comprehensive experiment with the human body whose only parallel is in Picasso.