Section 720 ILCS 5/1-2 - General purposesThe provisions of this Code shall be construed in accordance with the general purposes hereof, to:
(a) Forbid and prevent the commission of offenses;(b) Define adequately the act and mental state which constitute each offense, and limit the condemnation of conduct as criminal when it is without fault;(c) Prescribe penalties which are proportionate to the seriousness of offenses and which permit recognition of differences in rehabilitation possibilities among individual offenders;(d) Prevent arbitrary or oppressive treatment of persons accused or convicted of offenses.