A scientist wants to find out what kinds of fish live in the sea.
So, she rows her boat out to the middle of the ocean. She puts on her snorkel mask and jumps in the water. She is determined to catch the first fish she sees, no matter how big or small it is.
She lives in a world where the sea is endless, and the fish occupy an infinite amount of space. How many fish occupy that space? Is there one big, never-ending fish? Are there lots and lots of small ones?
Immediately, she notices a fish swimming beside her. He's one foot long, and as wide as her hand. She catches him. She brings him back to her boat.
Suddenly, the scientist realizes she's run out of time. She won't be able to catch any more fish.
So, she examines the one she has.
He's not too big, not too small. He's limited in his spatial dimensions, the scientist thinks, just as the life I'm living is limited by time.
What conclusions can the scientist, looking at this one fish, make about the kinds of fish that live in the sea?
Does she assume that this small fish is the only one of his kind? That he is alone in the endless sea, sandwiched between two large and never-ending fish that extend in opposite directions forever and ever?
No, that would be silly.
The scientist knows that the followers of some religions, and certain atheists, make similar conclusions about the kinds of lives that make up their eternity. Each of them believes his short life on Earth comes after an immeasurable time of non-existence, and comes before a never-ending after-life.
The scientist, alone in her boat, thinks: I may live to be eighty years old. If the religious experts were right, and if eternity lasted only five billion years, then there would be a 0.0000016 % chance I'd be alive right now.
But, eternity lasts more than five billion years. Eternity lasts forever. My eighty years in this world would represent 0.0000000 % of eternity. If the religious experts were right, there's no way I could be standing in this boat at this hour, holding this fish. It's an even sillier idea, she thinks, that I would be eternally rewarded or punished for the things I do during this 0.0000000 % of eternity. Who would believe such a thing? A child?
She returns her attention to the fish.
She understands that, if this fish has height and width limitations yet she randomly discovered him, it means every fish must have similar limitations. Some may be bigger. Some may be smaller. Some may be limited by foggy lines made out of jelly. Some are no doubt the same species as this one: yellow and shiny, with blue lines on their sides. Some fish may even be his exact copies.
But, no fish could be infinitely large and endless. If there were such a fish, it would've pushed into the space of this small one, and she would've discovered the endless fish and not the small one.
The scientist's thoughts turn to her own life and what lives will follow it. She understands that, like her life in this world, every other life will be limited by time. The existence of time proves that all lives are temporary. Only my soul, thinks the scientist, is unaffected by the passing of time.
She considers that her soul may go on to live lives lasting thousands of years. It may live lives that last five seconds each. It may experience consciousnesses that don't begin with births nor end with deaths, and which don't resemble Earth lives at all except that they're temporary. Her soul will live the lives of the people who share her world with her: her family members, her boyfriends, her fellow scientists, and the people who annoy her. Before eternity ends, her soul will experience all these things, and this life of hers as a scientist, many times.
She says to herself:
"Your soul is a fish. More specifically, your soul is all the fish in the sea. Your soul is also the powerful sea that created these fish."
She looks again at the fish she's holding. She notices an intelligent look in his eyes. And he's smiling.
He knows, the scientist thinks. He knows that he's actually all the fish in the sea. And he acts accordingly, to make the sea a better place for all.
He knows, thinks the scientist, he has the power of the sea that created him inside of him. He knows he created himself, and his friends, and this beautiful world to swim around in. He's small, but with this knowledge he's powerful. He doesn't need fancy possessions nor great accomplishments to make him feel good about himself. He's happy when he can eat, be warm, and share love.
She drops the fish back into the ocean. He swims away.
The scientist rows back towards her home. She's happy she learned what kinds of fish live in the sea.