https://wildfiregames.com/forum/topic/36934-civ-differentiation-athens/?tab=comments#comment-419889
Taken from this thread.
Athenians were known to be a civilization that values education, so this bonus attempts to reflect that.
A problem is that while all the values work ingame, the Structure Tree displays every technology with only a 5% discount,a 15% discount, so P1 and P2 technologies show a 15% discount. I suppose it's better than every tech showing a 5% discount as it can be argued that they can be skipped until P3. so P3 technologies only show a 5% discount.Although, phase up upgrades can't be skipped and the structure tree will show them as cheaper than they actually are.
I'm sure that wording can also be improved.