The Thomas Theorem describes the phenomenon in which human beliefs about reality can shape reality to align with those beliefs. One type of “self-fulfilling prophecy” that can be used to validate the Thomas Theorem is consumer product shortages during times of crisis. During a high-stress situation when people have limited control over their circumstances, they often try to exert control wherever they can. As rumors circulate that everyday necessities are in short supply, people become fearful that these products will no longer be available at all. They respond by buying large quantities of such supplies and hoarding them. By doing so, the people who excessively consume these items actually create a shortage as well as drive up prices.
A classic example of panic buying that leads to shortages is provided by toilet paper. In the United States, during two periods of national crisis, consumer lack of confidence created a run on the stores, and shelves were soon empty of toilet paper. This occurred in late 2001 after the September 11 attacks and during the 2020 Covid-19 pandemic lockdowns.