(a) A person "acts knowingly, " or with knowledge:

    (1)    With respect to his conduct or to attendant circumstances when he is aware of the nature of his conduct or that those circumstances exist; or

    (2)    With respect to a result of his conduct when he is aware that his conduct is practically certain to cause that result.

    (b) A person "acts purposely, " or with purpose, with respect to his conduct or to a result thereof when it is his conscious object to engage in that conduct or to cause that result.

    (c) A person "acts recklessly" or is reckless when he consciously disregards a substantial and unjustifiable risk that circumstances exist or that a result will follow and such disregard constitutes a gross deviation from the standard of care which a reasonable person would exercise in the situation.

    (d) A person "acts with criminal negligence" or is criminally negligent when he fails to be aware of a substantial and unjustifiable risk that circumstances exist or a result will follow, and such failure constitutes a gross deviation from the standard of care which a reasonable person would exercise in the situation.

    (e) Except as provided in section 16-84, a person is not guilty of an offense unless he acts with a culpable mental state, that is, unless he acts purposely or knowingly or recklessly or with criminal negligence, as the statute defining the offense may require with respect to the conduct, the result thereof or the attendant circumstances which constitute the material elements of the crime.

(Code 1964, § 7.550)

     State law reference(s)--Similar provisions, RSMo. § 562.016.