Hello, SFIA audio listeners. In this month's Nebula exclusive, big alien theory,

we're asking the reason alien civilizations might be rare is because most aliens are huge.

To hear it and every episode early and ad-free, plus hours of bonus content,

check out go.nebola.tv slash Isaac Arthur and use my code, Isaac Arthur.

When we ask what humanity will become, we are not just talking about tomorrow.

We are asking about the next trillion tomorrows on billions and billions of strange new worlds.

The Road Ahead.

When we ask what Humadi will become, we're really asking two questions,

what happens the next few generations, and what happens the next few million years,

or billions or trillions of years.

Those two horizons, the near and the unimaginably far, are separated by an ocean of possibilities, and yet both matter,

because the choices we make now echo across that vast future. Welcome to science and

futurism. I am your host, Isaac Arthur, and today will explore the branching pathways of our destiny.

We'll start with the oldest stream of all, extending our lives, not merely by decades,

but by centuries or even indefinitely.

We'll consider how artificial intelligence might merge with us, reshaping our minds into

something greater or stranger.

From there, we'll move into the broader world of transhumanism, enhanced senses,

stronger bodies, sharper minds, and whole societies built around augmentation. Beyond that,

lie the stranger post-human paths, hive minds, uploaded civilizations, beings that stretch across

planets or even stars, and all of this happens

against the backdrop of humanity's outward migration, into the solar system, into other stars,

...