Hello, thank you for taking the time to post your question!
The missing blanks here are Adam Smith and invisible hand, making the full sentence
According to Adam Smit, self interest and competition act as an “invisible hand” guiding firms in a market-based economy.
The invisible hand can be thought of how self interest and competition work together to produce what society needs in the most efficient way possible.
Hopefully that gets you moving in the right direction! Feel free to reach out for a lesson if you have any questions beyond that! :)
