Is-Ought

The is-ought fallacy occurs when a conclusion expressing what ought to be so is inferred from premises expressing only what is so, in which it is supposed that no implicit or explicit ought-premises are need. There is controversy in the philosophical literature regarding whether this type of inference is always fallacious.

Example:

He's torturing the cat.
So, he shouldn't do that.

This argument clearly would not commit the fallacy if there were an implicit premise indicating that he is a person and persons shouldn't torture other beings.