Geothermal Power

It occurred to me in the cold heights of my bathroom (where someone saw fit to leave the window open throughout a snowstorm) that geothermal power is a really, really, really, dumb idea.

"B-but it doesn't create any pollutants! It's natural! It's eco-friendly, man," one might retort.

Those are all good points. Except the last one. The last one is as short sighted as many eco-geeks are. I will now guide you through the reasoning why making ventures in geothermal power is a bad fucking idea.

1. The Earth was created well over 4 billion years ago. (Argue. I dare you.)
2. When the Earth was created, it was very rather warm.
3. The Earth today is rather cool in comparison, however the centre is still molten hot.
4. The molten hot centre is made of iron which, while moving, creates a magnetic field.
5. This magnetic field shields the Earth from many of the Sun's rays that are harmful to living things both directly and indirectly.
6. Recall the previous data: Earth was hot, but cooled. The centre of the Earth is hot. If we extrapolate this data we can predict that the centre of the Earth will cool.
7. Recall point 4. If the centre of the Earth cools, it stops being molten. If it stops being molten, it stops moving. If it stops moving, it stops creating a magnetic field.
8. Recall point 5. If there is no protective magnetic field around the Earth, then the harmful rays from the Sun will reach the surface.
9. This is the most important point. You and the majority of the living things you want to be eco-friendly towards live on the surface of the Earth.

So tell me, why exactly do we think it's a good idea to punch holes into the surface of the Earth and vent out all the heat? Because it's such a huge source of energy that we'll never use it all? Yeah, you said that about fossil fuels.