If so, the inequality diagnosis opens up interesting possibilities for policy solutions. The researchers found another interesting effect  a "trickle up" flow of wealth quite different from the usual "trickle down" picture of supply-side economics. In an economy with appreciable inequality, capital tends to flow from those with less to those with more, generating a cascade of transactions along the way. Hence, policy interventions aiming to spur economic activity should work better if they inject money into the system at the lower end, rather than from the top.