Much of the discipline of psychology has been developed by White, middle-to-upper class men. To what extent do you think that matters in how we think about psychology as a discipline? Are there advantages or disadvantages of this history?

Not everyone can live like an upper class white man. They posses privaleges  and live in a different mindset compared to for example a lower class woman or a man of color. Therefore you cannot compare a white middle class mans mental state as opposed to many other different peoples.

Explanation:

i believe the answer is: returns on investments, no wages

people who belong in upper class society would most likely get there by obtaining multiple source of income, which a certain percentage of ownership for businesses. since most of them are job creator, they would most likely get their money from profit, not wages.