The saying 'Jack of all trades, master of none', is often used as a snarky put down to generalists who dabble in multiple areas rather than have a singular focus or skill. But in his book Range, journalist David Epstein reveals that the full saying is actually 'Jack of all trades, master of none, though oftentimes better than master of one.'
He explains how having broad interests and a wide experience is far better for the individual and for society than being fantastic at one thing and rubbish at everything else. I'm only part way through but it contains some fascinating insights that apply to writing, creativity, research, education and life in general.
Range: How Generalists Triumph in a Specialised World