I don’t suppose anyone would argue with the proposition that the wheel is the most important invention in the history of mankind. However, I would suggest that the compass is up there with the wheel as a significant invention because of its impact on exploration.
The compass was discovered in 10th or 11th century China when someone realised that a lodestone suspended from a thread always pointed the same way. What a ‘Eureka’ moment that must have been!
Unfortunately the Chinese marketing organisation of the day didn’t immediately see the navigation application as worthy of pursuit, seeing more potential in the Feng Shui application. So property developers concerned with the spiritual well being of their building’s occupants, rather than explorers, were the first beneficiaries of this new technology.
Eventually, however, word spread of the lodestone phenomenon and the compass was put to proper use and the rest is history.
Then came GPS, but that’s another story.