What are Philosophers buildings for?

[turinkin]

the philosophers building (stoa stoics and such i think) are terribly expensive to build and maintain and give very little in return compared to other buildings (for pergamon at least).
i figured they give some hidden bonus (such as it gives positive traits to characters) or they would be kinda pointless.
maybe i missed some explanation somewhere but if some one could explain that would be great thanks!
that also applies to all other buildings that seem to have hidden uses (such as some governing/main settlements buildings that have yellow thingies that say something like "autonamous")
excellent game (too big to be called a mod)

[Sheridan]

That is right, traits in particular are a major gain from stoas, apart from the fact that some of them do provide a net income and some income and happiness modifiers. Stoas are set up to their own unique traits; a character that builds a stoa of a particular type (or simply governs that region for long enough) has a chance of picking up a trait specific for the philosophical school. Moreover, stoas (and libraries) increase the chance of getting many useful traits whether you aim to become a capable governor or skilled general: Inventive, Philosopher, Mathematician, Philanthropist, Rational and more. These are some of the best traits in the mod, and may really make these buildings worth it in the longer term.