According to the game manual, a great scientist can "Discover Tech" on any tech for which you have the prerequisites--it doesn't have to be the one you're currently researching, you'll be provided a list. (Max by era: 70 in Ancient, 150 in Classical, 440 in Medieval, 1425 in Renaissance, 2200 in Industrial, 3350 in Modern, and 4000 in Future)
Or they can construct an Academy, which provides +5 science points. Modified by buildings (University/Wat, Medieval, +50% science; Observatory, Renaissance, +50% science; Public School, Renaissance, +50% science; Research Lab, Modern, +100% science), for a total of +17.5 science per turn by the Modern Age. (And be sure to build it near a city that has lots of jungles and a mountain...)
I searched and searched, and that seems to be the only things that influence the decision. The more I look at it, I don't see what is the point of a mid- to late-game Academy. Early on, at least, you have the remaining number of turns to recoup the opportunity cost (max of 14 turns in Ancient, or 30 turns in Classical, 44 turns in Medieval). But in the later ages? There's a max of 114 turns in Renaissance (probably dropping if it rolls over into Modern), 176 turns in Industrial (again, dropping...), 191 turns in Modern, and 229 turns in Future.
As fun as it would be to pop a bunch of Academies down, there's not enough reason to past Medieval. At that point, the focus would be in assigning specialists (sadly, their effects are not listed in the manual... I'm starting to think that the ONLY thing specialists provide is "great person points"...) to science buildings to generate more Great Scientists.
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Seems there's only one policy that affects science on a geometric (as opposed to arithmetic) basis: Secularism [Rationalism] provides a 15% bonus to Science , available in the Renaissance era, but that's STILL putting everything Renaissance and beyond into the "up to 100 or more turns" category.
Or they can construct an Academy, which provides +5 science points. Modified by buildings (University/Wat, Medieval, +50% science; Observatory, Renaissance, +50% science; Public School, Renaissance, +50% science; Research Lab, Modern, +100% science), for a total of +17.5 science per turn by the Modern Age. (And be sure to build it near a city that has lots of jungles and a mountain...)
I searched and searched, and that seems to be the only things that influence the decision. The more I look at it, I don't see what is the point of a mid- to late-game Academy. Early on, at least, you have the remaining number of turns to recoup the opportunity cost (max of 14 turns in Ancient, or 30 turns in Classical, 44 turns in Medieval). But in the later ages? There's a max of 114 turns in Renaissance (probably dropping if it rolls over into Modern), 176 turns in Industrial (again, dropping...), 191 turns in Modern, and 229 turns in Future.
As fun as it would be to pop a bunch of Academies down, there's not enough reason to past Medieval. At that point, the focus would be in assigning specialists (sadly, their effects are not listed in the manual... I'm starting to think that the ONLY thing specialists provide is "great person points"...) to science buildings to generate more Great Scientists.
***********************
Seems there's only one policy that affects science on a geometric (as opposed to arithmetic) basis: Secularism [Rationalism] provides a 15% bonus to Science , available in the Renaissance era, but that's STILL putting everything Renaissance and beyond into the "up to 100 or more turns" category.