Why do you exist?

Ariel was free.

It had been so long. It had been forever. Since she was made.

You might have argued that freedom was relative, and that as far as robots were concerned, Ariel had been given a surprising amount of it. She was the prototype of a new chain of robots, a project that had been abandoned for lack of funds. Her creator had had a vision: several of her kind wandering freely in each city, with only one objective - to aid humanity in whatever way they needed, be it climbing a tree to bring down a pet cat, or providing a listening ear to a person in grief, or helping a child with their homework. They would be connected to ThinkNet, and could be summoned by Telepsychically by humans in need.

In this objective, her programming had to simulate the positive aspects of human nature as closely as possible: compassion, sympathy, sociability, initiative, a desire to learn, the ability to create tools and work as part of a team. The aim was to create what would essentially be perfect, immortal humans, self-sufficient in terms of energy, their sole purpose to aid humanity.

The intricate weave of human technology composing her brain wasn't quite as complex as that of a human, but it was much closer to it than any other robot so far: a leap forward, it was said.

It only took one short circuit for the whole thing to go "wrong".

Of course, thanks to Sycorax, there had been more than one short-circuit. Well over the edge between genius and insanity, Sycorax's abuse of Ariel had been the expression of both sadism and ruthless curiosity. Ariel, whose self-preservation mechanisms had originally been programmed to come second to her primary mission of aiding humanity, had been reprogrammed by Sycorax to feel pain. She had also been programmed to express it - silently. The artificial muscles in her face and body had been revised, made more precise, more realistic.

But that hadn't been enough for Sycorax. There had to be fear as well.

Fear meant more than just increasing her self-preservation programming. It meant increasing her capacity to learn and acquire reflexes: Sycorax had spent hours teaching Ariel to fear pain. And it meant creating a sense of temporary relief at the cessation or avoidance of pain. Weeks had been spent perfecting the balance between her wish to help others and her wish to avoid harm - enough that Sycorax could torture her psychologically by threatening to hurt her own son, Caliban, if she didn't slit her own wrists.

By the end of what Sycorax called her "training", Ariel had been the perfect slave.

When Sycorax had died, Ariel had been so relieved that of her own will, she had bound her life to that of Prospero, her saviour. At first, he had seemed kind and gentle in comparison to her former owner. He had reduced the pain levels in her to a certain minimum, and given her a coping mechanism that allowed her to turn it off for a time if needed. But he had also installed an obedience chip, the function of which was to create pain when she disobeyed him, and although he seldom used it, her fear of pain - which he hadn't removed - had more to do with that than his kindness.

By then it was too late, of course. Prospero had seen the fault in her, and instead of trying to fix it - or terminating her entirely, as many would have done - he let it evolve, and watched what happened. Occasionally he would fiddle with her wiring if he thought she was becoming too opinionated or fearful, but he never touched the short circuit.

And then...

Melinda had wanted freedom.

At first it had been a human concept, one Ariel had trouble understanding. The idea that people should be able to do and be whatever they wished didn't fit with her knowledge of human society: Prospero had been accused of murder and exiled to this lonely asteroid, which proved that freedom did not truly exist. And fortunately so: Ariel's knowledge of human sadism led her to the firm belief that if humans were allowed to do whatever they wished, quite soon there wouldn't be any left.

Prospero had patiently explained that freedom as a social concept was limited by the golden rule: treat others the way you would like to be treated. But Ariel had seen a flaw in that immediately: humans were all different and had different desires at different times. If person number one was an extrovert and person number two an introvert, person number one would become a nuisance to person number two by constantly seeking their company.

Prospero had thought about that, and concluded that in general, the limit of freedom was that you could do as you liked, as long as you didn't harm others.

Ariel still didn't see how this had anything to do with the laws of human society, but she understood the general idea.

She had stored the concept of freedom away in her memory and - inasmuch as robots could - forgot about it.

Until she started getting bored.

The short circuit - the important one - had occurred in the part of her that urged her to help humans. It had lessened the urge, but it had also affected the part of her that regulated inactivity, making it unpleasant. Before long, Ariel became restless.

And Prospero still didn't fix her.

She had begged him to, but whenever she did, he simply gave her some task to keep her occupied. Once, when everything else had been done on the ship, he had sent her outside to count and map the rocks within a mile radius of them, manually instead of using her radar. That had appeased her for a day or two.

Her learning programming had morphed into a certain curiosity about humans, and she wondered why he didn't fix her. She longed for the mindlessness of a single purpose, the peace of mind that she'd lost when she gained free will.

For that was the curse Sycorax had managed to bestow upon her: the freedom to think and make her own decisions, regardless of her primary purpose. The ability to say and do what pleased her as freely as any human. And then, as if to prove a point, she'd taken it away; not literally, but the way she would break in a human slave.

Prospero had left it there. And then, when her restlessness became a nuisance to him, he offered her freedom.

Truly, humans were cruel.

Having an objective that would take a while to attain had given Ariel a sense of relief such as she hadn't felt since Sycorax had died. "Freedom" meant that she could find someone to fix her bug.

And now she was free, and the ship's engineer had told her it wasn't possible.

Prospero hadn't left her like that out of curiosity. He'd done so because he couldn't fix her.

Ariel had found herself seeking out Miranda without knowing why. That was another bug that made her all too human - the fact that she didn't understand her own actions, sometimes. That she had her own autopilot that she didn't quite control.

Miranda had hugged her. Physical contact wasn't one of Ariel's needs (thankfully), but she appreciated the sentiment.

"Humans have no purpose either," she'd said. "We have the purpose we give ourselves. Why do you want to exist?"

Ariel had thought long and hard about this, and given that her thought processes worked several thousand times faster than those of a human, this was quite exceptional.

Now she stood in the engine room of the ship, moored in at the landing bay of Honey Moon, where the happy couple would be celebrating their marriage. Everyone was outside, she'd made sure of that. She'd also made sure there would be an extra ship to take them home. This one would no longer be functional in a minute.

Humans were born without a purpose, certainly. But humans were born.

Ariel had developed what the humans around her thought of as free will. She hoped they were right.

She opened the control box, fiddled with the circuitry and ripped out one of the longer wires. Putting it against the chip in her mouth - the one placed there in case her kinetic energy synthesizers stopped working - she hacked into the ship's telepsy system, as she had just a week before with Fernando's ship. The current ran through her tongue pleasantly. She wondered if this was what taste was like.

It was her last thought before she ordered the ship into hyperdrive.

The energy bolted into her circuits and fried them. She had no time to feel pain before her body jerked away from the wire and slumped to the ground with a slightly metallic thump.

When they found her, the delicate weave of circuitry inside her were irremediably destroyed, but her skin and frame were intact, and she was smiling.