I saw someone use the term "GP farm," which i assume means a city that makes more and/or sooner Great Persons (by increasing Specialists, and thus GP points, right?) But I'm not clear on how/when to start 'Specializing.'
In the early and mid-game, i would think you'd want city growth over GPs (who eat but don't farm.) I thought that once my cities reach their maximum/optimal size (limited by food, health, happiness) there would naturally come a point at which excess people become Specialists and start to generate more GP points. As Civ4 encourages fewer/better cities, i've been working hard at maximizing my cities' growth potential (by "acquiring" every health/happiness bonus I can, and trading for the rest) and i'm reaching the late game with cities approaching size 20, wonderfully happy and healthy, but with precious few Specialists - MAYBE one Engineer...
It seems like the ai is creating GPs faster than i do (usually an indicator that there's some trade-off i haven't learned yet) so, I guess my question is, what's a GP farm? When do i cut into a city's growth to make parasites, I mean Specialists, or is there a type of city that is ideal for them?
Thanks again to Roland and Parkin and the other 'Specialists' who help us 'newbs'!
[And thanks to ggganz for the terminology clarification.

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