Guthrie's learning theory was based upon the idea that a stimulus followed by a certain response would, when the stimulus was repeated, elicit the same response. This would take place regardless of rewards or punishments. This was a major departure from the conditioning theories that had dominated cognitive psychology. Guthrie also believed that once a connection was made between stimulus and response, it would remain, and did not need to be strengthened by repetition ("reinforced," to use the terminology of cognitive psychologists.) Everything being equal, people will respond to stimuli in the way that they most recently did. The only reason that it would be forgotten would be because of external interference (i.e., more stimuli). This was known as the "contiguity principle," and it argued that all of human learning was based upon the association between stimulus and response.