Text: "Economics as a System of Belief" (J.K. Galbraith)

https://www-jstor-org.ezproxy.library.yorku.ca/stable/pdf/4537864.pdf?refreqid=excelsior%3Ad5859c9bd79a3c68b5ac14a2d72cef38

From this text John Kenneth Galbraith identifies two different concepts that help to explain control and power within capitalist economic systems. One is consumer sovereignty and the other is producer sovereignty. can you please explain in details what Galbraith means by each of these terms. Which of the two does Galbraith believe to be a "myth" and which one is the reality? Why does he make this claim? What are the implications of this argument? please explain in such a way that in broadens my knowledge of the text