We compare moderate-sized earthquakes (magnitude between 4 and 5) in stable continental regions: Eastern North America and the Korean Peninsula to explore the causes of those earthquakes far from the plate boundary faults. In the past 10 years or so, seismic station coverage in the two regions improved greatly. As a result, detailed analyses of those moderate-sized earthquakes in two continents with similar seismicity are available. The results of those studies provide improved understanding of causes of those earthquakes in stable continental interiors. It may be possible to outline new findings to form a new paradigm for the causes of the intraplate earthquakes.