1) Writing
The Pagans invented letters, writing, literature, fiction, fact books, even ink and printing press. Hard to top :-D
2) Surgery
Saves lives, and have been saving and improving lives since Pagans invented it a couple of thousand years ago. Pagans also invented the rest of medicine, or most of it. Thank a Pagan every time you go and see a doctor or take medicine.
3) Astronomy
and navigation, sailing, ship building, aviation, space travels, moon walk... all thanks to Pagans.
4) Democracy
The Greek had it, the Vikings had it... also freedom of religion, freedom of speech and practically all civil and human rights. Lovely things :-)
5) Tolerance
Multiculturalism, diversity, tolerance, openmindedness, curiosity, will and ability to learn... the Romans especially were amazing with their ability to adapt and adopt... Really, if you go to meet other cultures with the idea of that they are stupid, primitive and lesser wilds, you won't learn anything from them.
6) Drums
Frankly, Pagans "invented" all music, but drums are my favorite.
7) Visual art
Cave paintings might not be advanced, but they do engage you, even today... And the Greek sculptures... or Scythian sculptures. Or Indian sculptures, or Chinese or... well... most Pagan sculptures are amazing :-)
I fully appreciate the beauty of nature, but mankind has beautified the world.
8) Pantheon
or Newgrange, the seven wonders of antique world, Great Wall of China; or a lot of other Pagan buildings. Frankly, we have to thank Pagans for the fact that we have houses to begin with.
9) Animal husbandry
Thank Pagans when you pet your cat ;-)
10) Zero
and the principles of mathematics. But zero is... divinely beautiful in its perfection.
Also, Pagans invented the wheel, cooking, metallurgy and all the other crafts, agriculture, irrigation, laws and hundreds of other things. Heron inventor would be a reason in himself.
Also, mead. Claude Lévi-Strauss thought the invention of mead as a marker of the passage "from nature to culture".
If you appreciate ANY of these things in your life, thank a Pagan. ;-)
