I’ll give you an example that happens in physics all the time.
Acceleration and force.
If you know the individual forces acting on an object you can find the net force. Then with the net force you can absolutely determine the acceleration they will create. You use the forces to deduce the acceleration.
This is like when you see a person push a box. You see the push, know how hard it was pushed, and knowing the mass of the box you can calculate the acceleration.
If you see an object accelerate you can infer a net force was present. But you can’t be absolutely certain as to the individual forces that make it up.
In our box scenario you’d see the box accelerate, then make a claim as to how hard it was pushed. But you may have forgotten about friction…
Even more odd, you see a box rise into the air, slow and then gain speed on the way down. You don’t see anything touch the box. So you *infer* that a force must be accelerating it downwards (gravity) even if you can’t see the source of it. This is a sound inference, as the only other times you see acceleration are when a direct force is applied (pushing/pulling).
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