Where did the idiom gut feeling come from?

The idiom "gut feeling" originates from the belief that the stomach is a center for intuition and emotions. Historically, many cultures associated physical sensations in the stomach, like butterflies or nausea, with instinctual responses to situations. This connection likely stems from the body's physiological reactions to stress or excitement, which can manifest as feelings in the abdomen. Over time, the phrase evolved to describe an instinctive judgment or intuition.