the authors purpose was to make us understand that many religions mind has its own reaction. that people with different religion brain, function more different than others. that they cannot prove that god is real or not. the only way they can do that is that the people choose if god is actually real or not, if any other things that other religions worship is real. the author wants the reader to think what side are you on. the author used different test subjects in different environments to check if the brain reacted different. that faith is something you believe in but can be proven in science. that the brain of these people in these different religions are the same or differ. that in some cases religion is chosen in life or death situations
