Ideas ahead of their time

Imag­ine a per­son in the an­cient world who came up with the fol­low­ing idea: “What would the sun and moon look like if they were very very far away?” This idea would likely lead to the con­clu­sion that they would look like tiny points of light, which then could lead to the ques­tion “What if the tiny points of light we call stars and planets are ac­tu­ally far­away suns and moons?”

Un­for­tu­nately, our an­cient friend would likely be stuck at that point, due to the limi­ta­tions of hu­man vi­sion and the lack of proper in­stru­ments for ex­am­in­ing the na­ture of ce­les­tial ob­jects. But our friend would be right, un­like nearly ev­ery other hu­man un­til Gior­dano Bruno’s cos­mol­ogy of 1584.

My ques­tions then are, what other ideas of similar power ex­ist, how will we know them if we find them, and is there any way to search for them in­ten­tion­ally?