What is the most important actor in a capitalist economy?

I'm reading about the Mondragon Cooperative in Spain, and their success is making me wonder. Is it the laborer, who actually creates the product, or is it the capitalist, who uses risk to make the investment, and oversees the creation of the product?<br><br>I'm asking seriously, and without any agenda. I'm very interested in this and would like to hear your thoughts.