An action which is opposed to a previous action?

Answer:
This sounds a bit like Newton's 3rd Law of Motion, which states:

"To every action there is always an equal and opposite reaction: or the forces of two bodies on each other are always equal and are directed in opposite directions."

It is a law of motion, the 3rd one specified by Sir Issac Newton in 1686.
Contributor: Bravewriter
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