the temperature

A few metres down, the ground stays close to the same temperature all year. Up on the surface you get "summer" and "winter" and you have to own two coats. Underground you own zero coats. I have hated seasons for a long time and now I have science.

there is a whole town that agrees with me

In Coober Pedy, in South Australia, loads of people live in homes dug into the hillside, because it is cooler than living on top of it. They have underground churches. They have an underground hotel. They are fine. They are better than fine.

we already did this and then forgot

Derinkuyu, in Cappadocia in Turkey, is an underground city many floors deep, carved out of soft rock more than a thousand years ago, with room for thousands of people and their animals. They had stables down there. Then everybody just went back up?? To be rained on??

no weather

Rain is the sky leaking. Underground the sky cannot reach you. (Sometimes it does reach you. That is called flooding. We do not talk about flooding at meetings.)

the sun

The sun is a lamp you can't switch off and it gives you a rash. Down here we have the headlamp, which has a button.

property

Land is expensive. But the land under the land is RIGHT THERE and nobody is using it. I have been told this is "not how property law works". I am appealing.

neighbours

My neighbours would be worms. A worm has never once asked me what I do for work.

common objections (wrong)

"What about vitamin D?"

Mushrooms have vitamin D. I will eat the mushrooms. (I have since been told the mushrooms need sunlight to make it. I am choosing not to have been told.)

"What if the tunnel collapses?"

Then I will be more underground, which was the goal.

"Have you personally lived underground?"

I have dug a hole in my garden that comes up to about my knee and I stood in it for most of an afternoon. It was the best afternoon of my life.

I rest my case. I rest it in a hole.