They were shapes on a canvas, pale and waiting, until the Tree Shape stirred. Its inky branches stretched, fracturing the void into jagged shadows. "Without us," it rumbled, its voice like creaking timber, "there would be no structure. No bones beneath the beauty."

The Round Shape rippled beside it, translucent as a soap bubble. "But colour breathes," it chimed, its edges shimmering. "What's a skeleton without a heartbeat? Without golds that melt into purples, reds that argue with blues?"

A hushed murmur skittered across the canvas.

"Edges," whispered a small, rigid shape, pressing itself into the bottom right-hand corner. "Edges keep things safe."

The Tree Shape scoffed, a rustle of charcoal. "Safety is stagnation. Art is wilderness. Roots cracking stone. Branches clawing at sky."

"Yet even wilderness needs light," the Round Shape countered, softening to a buttery orange. "Imagine a forest dappled with dawn - darkness needs colour to be seen at all."

"Balance," hissed a curving shape, coiling like smoke. "Balance is the unspoken rule."

The Tree Shape bristled, its form thickening. "Rules? You speak as if art is a ledger. It is chaos - shapes colliding, colours consuming one another!"

The Round Shape dimpled inward, amused. "Chaos? Look at you, rigid as a tombstone. You've never bent in your life."

"Bending," sighed a wobbly muted turquoise shape, hovering in the background. "Bending is its own strength."

For a moment, the canvas hummed with tension. Then the Round Shape pulsed, its center blooming into a vibrant reddish orange tint. "What if we're both wrong?" it ventured. "What if art isn't shapes or colours, but the quarrel between them? The way a shadow deepens a hue, or a curve mocks a straight line?"

The Tree Shape hesitated, its branches thinning to wispy greenish blue. "An interesting theory," it conceded, grudgingly. "But without shapes, colours would spill into nothingness."

"And without colours," the Round Shape replied, twirling into a playful cerulean, "shapes would be a prison."

"Together," whispered a dark blue shape behind the Round Shape. "Together, you make a world."

The shapes fell silent. The Tree Shape's branches softened into smoky tendrils; the Round Shape blushed a tender rose, its light spilling into the shadows. Around them, the whispers swelled - shapes humming of tension and murmuring of mystery - until the canvas thrummed with a silent, electric language.

Then, from beyond the void, a brush dipped.

The Tree Shape stiffened. "What's that-"

"Shh," glowed the Round Shape, now gold again. "It's the Artist. Let's see what we become together."

The first stroke was black - a trunk. The second, a burst of orange - in the Round Shape's embrace. Whispers melted into highlights, shadows, textures.

And when it was done, the shapes didn't argue. They simply were - a storm and a sanctuary, a debate and a duet.

Art, after all, had room for all of them.