In science, action is the product of work and time: [1]

 A = Wt \,

where A here stands for "action", W for work, and t for time.

Philosophy
In philosophy, generally tracing to the human movement theories of Greek philosopher Aristotle, what is called “action theory” or theories of “action” attempt to debate or theorize about “will” in the context of materialism, physicalism, and or other types of non-reductive chemical physical materialism, often alluding to the notion that “free will” and or consciousness or conscious “choice” to make an action are aspects of an emergent property. [2] Cuban-born American philosopher Alicia Juarrero puts it like this: [3]

“The philosophical literature of action has remained trapped in [a] peculiar combination of Aristotelian and Newtonian views of causality.”

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See also
Action chains
Action thermodynamics
Mechanical action

References
1. Perrot, Pierre. (1998). A to Z of Thermodynamics (pg. 4). Oxford University Press.
2. Deacon, Terrence W. (2011). Incomplete Nature: How Mind Emerged from Matter (action, 35+ pgs). W.W. Norton & Co.
3. Juarrero, Alicia. (1999). Dynamics in Action: Intentional Behavior as a Complex System (action, 95+ pgs). MIT Press.

Further reading
● Osborn, Henry F. (1916). The Origin of Life: on the Theory of Action, Reaction and Interaction of Energy (pg. xi). The Science Press.
● Kennedy, Ivan R. (2001). Action in Ecosystems: Biothermodynamics for Sustainability (ch. 4: Action Thermodynamics, pgs. 65-98). Research Studies Press.

External links
Action (physics) – Wikipedia.
Action theory (philosophy) – Wikipedia.
Social actions – Wikipedia.

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