Here is a lovely data driven answer, if you are looking in the US and are willing to use political data as a proxy for 'thriving intellectual community': https

Here is a lovely data driven answer, if you are looking in the US and are willing to use political data as a proxy for 'thriving intellectual community': https://beta.observablehq.com/@jake-low/how-well-does-population-density-predict-u-s-voting-outcome https://beta.observablehq.com/@jake-low/how-well-does-popula...