There are two mechanisms that stabilize the economy automatic without action by government authorities.

Progressive income taxes

Mentioned in Reduce poverty and Inequality. The two scenarios:

• During inflationary periods, income rises. The income that is taxed rises proportionally more, slowing down the increase in Aggregate Demand.
• Similarly, in recessionary periods, the income that is taxed decreases, reducing the decrease in aggregate demand.

Unemployment benefits

• In a recession, the unemployment increases, while unemployment benefits increase. The increase allows the unemployed to maintain the level of consumption to some extent, slowing the blow of decreasing Aggregate Demand.
• During inflationary periods, the unemployment benefits decrease, leading to a smaller increase in aggregate demand.