Final answer:
Introducing a second teacher into Milgram's experiment would likely decrease obedience as it would allow for communication and mutual reinforcement of moral concerns, thereby challenging the authority of the experimenter.
Step-by-step explanation:
If there had been 2 teachers and a student in Milgram's experiment, the teachers may have been able to compare ideas. This would probably decrease obedience. The Milgram experiment demonstrated that obedience to authority figures played a significant role in the willingness of participants to administer shocks to learners. However, variations of the experiment indicated that when the connection between the teacher and learner was more personal or when the authority of the experimenter was less immediate or less prestigious, obedience decreased.
Comparing ideas often leads to individuals challenging authority and the status quo. By discussing the situation with each other, the teachers might have reinforced their moral concerns and questioned the validity of the orders given by the experimenter. This social support, even in the form of comparing notes, could result in a greater likelihood of resistance.
In several variations of the Milgram experiment, changes that made the humanity of the person being shocked more salient led to a decrease in obedience. When teachers were in the same room as the learner or had to touch the learner's hand, or when the experimenter gave orders by phone, the obedience rates dropped. This suggests a dynamic where increased empathy or reduced authority presence undermined the obedience that was observed when the teacher was alone with the experimenter.