From Wikipedia:

shy and self-effacing, with a contrarian streak that his friends find refreshing but his intellectual opponents find exasperating. “I have the sense that when consensus is forming like ice hardening on a lake, Dyson will do his best to chip at the ice”, Steven Weinberg said of him. His friend the neurologist and author Oliver Sacks said: “A favourite word of Freeman’s about doing science and being creative is the word ‘subversive’. He feels it’s rather important not only to be not orthodox, but to be subversive, and he’s done that all his life.”

I was vaguely familiar with the Dyson sphere, but on reading a bit more about him, i’m now intrigued to find out some more.

Just ordered his memoir, ‘maker of patterns’, so thanks for pointing me in that direction.