Figuring out 2nd order consequences is especially pertinent in financial markets, whose complexity leads to ripple effects being felt in unexpected ways.
2nd order thinking is considering the consequences of the consequences of an action. Acting without regard to these can lead to large unintended consequences.
Do low rates lead to higher stock prices? The logic goes: low rates give us higher present values and thus lead to higher equity values. Is this argument valid?
Paradigm is the most important part of the Iceberg model. It exists on an ideological level but manifests itself physically through all the layers above it.
The Iceberg model is a great tool to help you think in terms of systems. It has 4 layers, events, patterns of behavior, systems structure, and paradigm.