# Why do a conservative force try to reduce potential energy?

Mathematically I understood the reason why, for a conservative force, $\vec{F}=-\vec{\nabla}U$.

Physically this means that a conservative force is always oriented in the direction of greatest decrease of potential energy.

What I do miss is the physical reason why a conservative force do so (i.e. tries always to reduce the potential energy). I tried to look at it in terms of the work done by the force but I could not really find a good physical explanation for that.

So the observation is rather: the potential energy decreases fastest in the direction of the force; which now is obvious, since for a given magnitude of $\mathrm ds$ the work (scalar product) $F\cdot\mathrm ds$ is maximal in the direction where $F$ and $\mathrm ds$ are parallel. Does that address your question?
• well, it is not a physical reason, it is rather computational, the work (scalar product) $F\cdot\mathrm ds$ is maximal in the direction where the two factors are parallel (... I edited the answer) – Ilja Apr 4 '16 at 10:58