Like, um, the friction against the ground that the object is moving on. Isaac Newton observed commonplace phenomena then figured out the scientific reasoning behind the phenomena then put it all into words that we now quote as time-tested & true scientific dogma.
![[gasp]](https://i.imgur.com/GyNGamC.png){kind=link}
I think the more interesting thing is that a moving object will keep moving at constant speed unless a force is applied to it.
Like, um, the friction against the ground that the object is moving on. Isaac Newton observed commonplace phenomena then figured out the scientific reasoning behind the phenomena then put it all into words that we now quote as time-tested & true scientific dogma.
Then Einstein comes in and says everything is moving at a constant spacetime velocity, and that friction isn’t a real force.
Friction is real, it’s the “force” of gravity that is an illusion.