Index -> Playing the Game -> The Game Screen -> Tech Status
In the lower-left corner of the map are icons representing your Tech Status (7) for each of the five techs in the game. A number next to each symbol indicates how much of that tech you have available to spend.
The values indicated are your current tech levels - not necessarily your maximum tech values. As you play cards and use activated abilities, the numbers next to the symbols will decrease. As you undo these actions, your tech levels will go back up.