How do great sages choose a tech?

[Alamoslithe]

I have tried to use great sages to pop a tech line, but the lightbulb tech always seems to be randomly generated.

Is there any way to change or control the tech that a great sage will discover with his lightbulb?

Or alternatively, how does the great sage determine which tech he will grant?

 

[xanaqui42]

I have tried to use great sages to pop a tech line, but the lightbulb tech always seems to be randomly generated.

Is there any way to change or control the tech that a great sage will discover with his lightbulb?

Or alternatively, how does the great sage determine which tech he will grant?

Here is a description of the lightbulb techs (with priority).

If you're interested in how to control them, the "lightbulbing" technologies are determined by a combination of the flavor of the unit, times the flavor values of each of those technologies. In the event of multiple unit flavors, I think that the values are summed.

So if you wanted to change Great Sage lightbulbing, the easiest way is to change the values in the CIV4TechInfos.xml file for the FLAVOR_SCIENCE values. Note that where absent, you can add them. While technically this affects the AI's choice of technology, the reality is that in Vanilla FfH II any value in the range of 1-10 here has very little impact; it ends up being way below the random component of the AI evaluation (my recollection is that at most, it has an impact equal to 20% of the random number).