If it is assumed that all behavior can be explained only by material causes such as brain neurotransmitters, then we must realize the consequences of this assumption. The central consequence would be the invalidation of any moral concepts such as “right and wrong,” “justice,” and “forgiveness” because these concepts suggest that there is a person making his or her own decisions on matters involving other people.
How can one even consider forgiving someone “who just could not help it” because of a particular brain function? The short answer is that we cannot even consider forgiving in such a scenario because to forgive is to say to oneself, in one form or another: “He did wrong, and in that wrong he hurt me. I will now try to show love for this person who acted badly.”
Enright, Robert (2015-09-28). 8 Keys to Forgiveness (8 Keys to Mental Health) (pp. 98-99). W. W. Norton & Company. Kindle Edition.