Voluntarily causing Hurt and voluntarily causing Grievous Hurt under Indian Penal Code are defined under Section 321 and 322 of Indian Penal Code 1860. Provisions under section 321 and 322 are:
Whoever does any act with the intention of thereby causing hurt to any person, or with the knowledge that he is likely thereby to cause hurt to any person, and does thereby cause hurt to any person, is said "voluntarily to cause hurt"
Whoever voluntarily causes hurt, if the hurt which he intends to cause or knows himself to be likely to cause is grievous hurt, and if the hurt which he causes grievous hurt, is said "voluntarily to cause grievous hurt."
Explanation- A person is not said voluntarily to cause grievous hurt except when he both causes grievous hurt and intends or knows himself to be likely to cause grievous hurt. But he is said voluntarily to cause grievous hurt, if intending or knowing himself to be likely to cause grievous hurt of one kind, he actually causes grievous hurt of another kind.
Illustration A, intending or knowing. himself to be likely permanently to disfigure Z's face, gives Z a blow which does not permanently disfigure Z's face, but which cause Z to suffer severe bodily pain for the space of twenty days. A has voluntarily caused grievous hurt.
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