The provisions of this code shall be construed in accordance with these general purposes.
(1) Forbid and prevent the commission of offenses.
(2) Define adequately the conduct and mental state which constitute each offense and safeguard conduct that is without fault from condemnation as criminal.
(3) Prescribe penalties which are proportionate to the seriousness of offenses and which permit recognition or differences in rehabilitation possibilities among individual offenders.
(4) Prevent arbitrary or oppressive treatment of persons accused or convicted of offenses.