Act and Intent

Every legal act is a combination of some type of act and some type of intent. For example, a "signature" is a combination of some writing or marking of one's name, nickname or initials or other symbol (the act) combined with a peculiar type of intent called the intention to sign (animus signandi). The intention to sign is a mental intention that the act be a "signature," i.e., that the formality and finality which accompany a signature be present.

—Robert L. Mennell, Wills and Trusts in a Nutshell (1994)