Full Idea
Law 3: To any action there is always an opposite and equal reaction; in other words, the action of two bodies upon each other are always equal and always opposite in direction.
Gist of Idea
3: All actions of bodies have an equal and opposite reaction
Source
Isaac Newton (Principia Mathematica [1687], Axioms)
Book Reference
Newton,Isaac: 'Philosophical Writings' [CUP 2004], p.71
A Reaction
Is this still true if one body is dented by the impact and the other one isn't? What counts as a 'body'?
Related Idea
Idea 24064 If something is pushed, it pushes back [Aristotle]