Re: If you could 'un-invent 'something...
Wheels.
1. It's wheels that allow us to import so much foreign produce instead of using our own.
2. Without wheels diseases wouldn't spread so easily, I mean human, animal, and plant diseases we import.
3. Families might be closer, instead of spreading out and hardly seeing each other.
4. No traffic jams or petrol prices to worry about, and we could use any horses manure on our veg patches!
5. People might be healthier if they had to walk to the shops/work/school.
But it would be a strange world without the wheel.