Harry thought of the stars, the image that had almost held off the Dementor even without a Patronus. Only this time, Harry added the missing ingredient, he'd never truly seen it but he'd seen the pictures and the video. The Earth, blazing blue and white with reflected sunlight as it hung in space, amid the black void and the brilliant points of light. It belonged there, within that image, because it was what gave everything else its meaning. The Earth was what made the stars significant, made them more than uncontrolled fusion reactions, because it was Earth that would someday colonize the galaxy, and fulfill the promise of the night sky.
Would they still be plagued by Dementors, the children's children's children, the distant descendants of humankind as they strode from star to star? No. Of course not. The Dementors were only little nuisances, paling into nothingness in the light of that promise; not unkillable, not invincible, not even close. You had to put up with little nuisances, if you were one of the lucky and unlucky few to be born on Earth; on Ancient Earth, as it would be remembered someday. That too was part of what it meant to be alive, if you were one of the tiny handful of sentient beings born into the beginning of all things, before intelligent life had come fully into its power. That the much vaster future depended on what you did here, now, in the earliest days of dawn, when there was still so much darkness to be fought, and temporary nuisances like Dementors.
And Harry's eyes stared directly at that which lay beneath the tattered cloak, looked straight at that which had been named Dementor. The void, the emptiness, the hole in the universe, the absence of color and space, the open drain through which warmth poured out of the world.
The fear it exuded stole away all happy thoughts, its closeness drained your power and strength, its kiss would destroy everything that you were.
I know you now, Harry thought as his wand twitched once, twice, thrice and four times, as his fingers slid exactly the right distances, I comprehend your nature, you symbolize Death, through some law of magic you are a shadow that Death casts into the world.
And Death is not something I will ever embrace.
It is only a childish thing, that the human species has not yet outgrown.
And someday...
We'll get over it...
And people won't have to say goodbye any more...
The wand rose up and leveled straight at the Dementor.
"EXPECTO PATRONUM!"
The thought exploded from him like a breaking dam, surged down his arm into his wand, burst from it as blazing white light. Light that became corporeal, took on shape and substance.
A figure with two arms, two legs, and a head, standing upright; the animal Homo sapiens, the shape of a human being.
Glowing brighter and brighter as Harry poured all his strength into his spell, blazing with incandescent light brighter than the fading sunset -
And someday when the descendants of humanity have spread from star to star, they won't tell the children about the history of Ancient Earth until they're old enough to bear it; and when they learn they'll weep to hear that such a thing as Death had ever once existed!
You are not invincible, and someday the human species will end you.
I will end you if I can, by the power of mind and magic and science.
I won't cower in fear of Death, not while I have a chance of winning.
I won't let Death touch me, I won't let Death touch the ones I love.
And even if you do end me before I end you,
Another will take my place, and another,
Until the wound in the world is healed at last...
Harry lowered his wand, and the bright figure of a human faded away.
Slowly, he exhaled.
Like waking up from a dream, like opening his eyes after sleep, Harry's gaze moved away from the cage, he looked around and saw that everyone was staring at him.