When gravity acts on an object it doesn't require energy, does it?

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Daniel Dennet in Consciousness Explained writes: Any change in the trajectory of an object is an acceleration requiring the expenditure of energy.

When gravity changes the trajectory of an object is doesn't require an expenditure of energy, does it?
 
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The fundamental forces, gravity, strong force, weak force, and electromagnetic force, do NOT require an expenditure of energy to work.

When we refer to things like gravity, we usually use Potential Energy and such. It takes work to move something away from a source of gravity, and in effect you get that energy back when it moves back towards the source.