At the beginning of the novel, Paul--like his classmates--is naive.  He does not understand the true implications of the war, nor does he understand what it will mean to be a soldier.  He is easily persuaded by Kantorek to join the war effort to show his service to Germany.  Once Paul and his classmates enter the war, several young men quickly lose their lives.  When Kemmerich loses his leg and suffers complications from his injury, Paul shows his loyalty by staying with Kemmerich until the last moment. 

Yet, even though the soldiers are thrust into horrible situations, Paul for a while remains idealistic particularly in his thoughts about nature.  He sees beauty in nature and feels like the earth provides the men with a sense of security. 

However, Paul quickly becomes disillusioned when he realizes that the men in charge of the war care nothing about the soldiers who daily lose their lives on the battlefield.  But Paul is not completely taken under by the war--while on the battlefield, he falls into a shell hole and out of fear stabs a French soldier to death.  While the man dies, Paul shows that he is compassionate by attempting to make the soldier comfortable (giving him water).  Throughout the novel, Paul's round character is presented through the various emotions experienced by a soldier during war.