1. Individual specialization
2. Agriculture
3. The alphabet
4. Logic/mathematics
5. Electronics/computers
Without 1 we wouldn't have 2,3,4,5,anything.
Without 2 we wouldn't have the ability to exploit 1 for progress.
Without 3 we wouldn't have the foundation for large-scale anything or #4.
Without 4 we wouldn't have the necessary tools for the progression of organization/science/technology/everything.
Without 5 we wouldn't have the most powerful tool yet invented, one which takes humanity's #1 asset, intelligence, and exponentially increases it over time. How can any list not include #5?