Stat bonuses from different items do not stack

[mechkg]

My character has base INT of 10. When I equip the following 2 items: helm with + 2 INT and armor with +1 INT I expect his INT to go up to 13. However this does not happen and only the helmet's bonus is applied. Is this a bug or by design?

[Klaus]

That's by the game design. In addition, defensive stats are same. 

[Arkh`Cthuul]

As the gametips repeatedly (loading screen, In Game) state that multiple bonuses to the same stat are usually not stacked, but the lesser one is supressed, I`d wager "Design".

 

A Design Decision I do not like, but well, what can you do?

[dirigible]

This is very inconsistent, though. Some equipment bonuses DO stack, and all equipment bonuses (I think?) stack with eating food.

[Emptiness]

If you open up the Character screen and scroll down to Active Effects you can see which effects on you are being suppressed (so that you can redistribute items, for example).