Countable Infinity, Uncountable Infinity

An old psychiatric hospital lay hidden amid dark, lightless mountain woods. Even the endless light and heat blooming from the blazing fireball above could not illuminate this shadowed place.

The quiet, eerie atmosphere made it feel like the set of some horror movie.

The two people, neither of whom looked remotely powerful, were like playful children who had wandered into a dangerous place—the sort sacrificed at the beginning of a horror film.

"Then again, muscular, sturdy adults in horror movies are generally there to demonstrate the irresistible power of ghosts and monsters."

"On the contrary, frail old men, truly adorable children, weak women bullied by others—these conventional weaklings often possess strange abilities to resist ghosts and monsters."

Li Heng looked up at the blazing sun in the sky. Even the light of Newton and Leibniz stopped before the gates of this psychiatric hospital.

The gates slowly opened to either side, revealing the scene hidden behind them:

A spacious courtyard. A jujube tree laden with large red dates stood in the yard, while a clear swimming pool held a deflated yellow swim ring, looking somewhat like Archimedes' bathtub from before.

It was an utterly ordinary scene, completely opposite to the grim and terrifying atmosphere they had felt outside. It was merely a very ordinary building.

"Although mathematicians and philosophers are often associated with the image of eccentric geniuses and mentally unstable madmen, Cantor completed most of his work establishing set theory and transfinite number theory while he was mentally sound."

"What we are exploring is naturally not Cantor in his later years, after he entered a psychiatric hospital, but the ideas through which he discovered transfinite numbers."

Li Heng led Achilles into the empty psychiatric hospital, his gaze falling upon the jujube tree covered in red fruit.

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