I was an econ major. I think partially the reason why they don't teach econ properly is that there is a inferiority complex when it comes to more rigorous hard sciences like physics. If you look at a modern econ textbook, especially macro, it's filled with equations to compute meaningless enigmas that predict nothing. It reminds me of astrology several hundred years ago where they too had complex charts and math... which they conveniently only understood...to predict nothing. I found econ to largely be a waste of time... Fortunately I double majored in math which led to a more fruitful line of work in systems engineering.

If you understand this simple concept, you will understand income inequality: banks lend money to people who don't need money. 

If the basis of your stimulus program is to make it easier to lend money, take a wild guess who that money goes to.... people who don't need money.