The problem has been economists’ obsession with trying to place price at the heart of economics. A theory of price requires mathematical modelling of people’s decision-making, which means that it’s going to fail if we can’t perfectly predict exactly what everyone is going to do (which we can’t). If we instead use balance sheets, and in particular net worth, as our fundamental concept, we can have a mathematical model of the economy which is independent of the decisions and actions of the participants, and we have something almost analogous to the principle of conservation of energy.

Most actions which increase one person’s net worth also decrease another person’s by exactly the same amount, and have no effect on anyone else’s net worth. The only exceptions are production (increase one person’s net worth without decreasing anyone else’s) and consumption (decrease one person’s net worth without increasing anyone else’s). The model can scale from a Robinson Crusoe right up to the world economy because there’s no fallacy of composition. Bubbles are quickly revealed as being based on insolvency, which is the only fundamental cause of crisis.

You can see some videos about the approach here