[...]most economic analysis is done at the level of entire economics, the macro or macroeconomics level. [...] The opinions are often based on massive data analyses, which attempt to find out what economic events occur at about the same time as other economic events. However, this co-relationship does not prove that one event causes the other in any sense that an ordinary person would use causality. Moreover, these analyses are usually unable to determine the direction the causality flows from one event to the other.

This is not true for microeconomics. Microeconomics is about the behavior of firms in the same market. These firms are in the same market because they're trying to sell the same goods and services to the same customers. Thus these firms interact intensely with the same customers and among themselves. The nature of these interactions is rooted in human behavior, which we understand something about intuitively and scientifically. Thus we can understand why firms and customers behave the way they do. That means we can understand causality within markets.

From The Power of Productivity: Wealth, Poverty, and the Threat to Global Stability by William W. Lewis