Sure there is. The concept is that if you allow the richest to keep all their riches, they will spend it on things which will stimulate the rest of the economy. Of course, this has proven to be a seriously misguided theory, with the actual results being a lack of consumer spending and concentration of wealth to the wealthy. Is that succinct enough for you? Now, whether a bonafide economist came up with this, or RR just pulled it out of his butt is another question...