. Raison : To untangle the mystery of patients ' symptoms , try to make the symptoms make sense . Tourette 's syndrome can be ruled out , since it 's a rare and solitary disorder , he says . He says environmental poisons , which are n't causes because tics affected well - adjusted group . At first glance , Tourette 's syndrome is an attractive explanation for the Le Roy tic epidemic . Raison : That gives psychological symptoms as most reasonable explanation .
. Raison : To untangle the mystery of patients ' symptoms , try to make the symptoms make sense . Tourette 's syndrome can be ruled out , since it 's a rare and solitary disorder , he says . He says environmental poisons , which are n't causes because tics affected well - adjusted group . Raison : That gives psychological symptoms as most reasonable explanation .