The act of an agent or efficient cause. 

Immanent Action.— An action that produces an effect within the agent. E.g., thinking, digesting, or conceiving an offspring.  For some scholastics, immanent action is technically a quality. 

Transitive Action (also called Transeunt Action).— An action that produces an effect outside the agent, with this actualization of the “patient” being the very action of the agent. E.g., the building of a house.  According to some scholastics, an act which is immanent (such as the act of knowing) is also virtually productive or virtually transitive, insofar as it involves the production of a terminus as a condition of the immanent action itself.  In the case of cognition, the “speaking” of the internal word or concept is considered a virtually productive action, while cognition itself is wholly an immanent quality. 

Voluntary Action.— In Aristotelian and scholastic usage, an action whose cause comes from within the agent. It applies only to human beings and other animals. 

Human Action (also called Human Act).— A voluntary action that a human being does knowingly and willingly, pursuing an end precisely as an end. 

Mixed Action.— A human action that is done under pressure of some kind. 

Involuntary Action.— An action that is forced upon the agent or that is done out of ignorance.  

Action of Man (also called Act of Man).— An involuntary action of a human being. 

N.B.— As concerns ignorance and regret, Aristotle distinguishes involuntary actions from nonvoluntary actions. Involuntary actions done out of ignorance are regretted. Non-voluntary actions are actions done out of ignorance but not regretted. (Nicomachean Ethics, III, 1).