Dialectics and Newton's Laws
Isaac Newton wrote three laws of motion.
Every object in a state of uniform motion will remain in that state of motion unless an external force acts on it.
Force equals mass times acceleration
For every action there is an equal and opposite reaction
These laws refer to motion of objects--from atoms and bullets to planets and galaxies. Dialectics also refers to motion of objects, but extends Newton's laws to all of nature, society, and thought. Let's compare Newton's laws to the laws the Frederick Engels used to describe dialectics:
This is pretty close to Newton's 3rd law. The forces holding up a bridge must be stronger than the gravitational and other opposing forces (wind, rain, earthquakes. . .) that could cause it to fall. To graduate from high school a student has to overcome all the opposing forces to reach that goal such as passing tests, showing up to class, writing papers, and following school rules. In politics, if we try to make changes to existing laws, we have to overcome the opposing reactions to our attempts. The most powerful thing we can change is our mind--to do so, we need to overcome all the weight of old ways of thinking.
This is similar to Newton's 1st law. If you are in a car approaching a red light, you need to apply the brakes to make the car stop. If there is a large rock in your driveway, you need to apply a force to remove it; it will not move unless the force you apply is stronger than the inertia/resistance of the rock to move. In politics, Frederick Douglas said, "Power concedes nothing"--in other words, unless acted upon by a political force strong enough to change it, the existing power structure will not change. In thought--when we do change our mind, it can open up a whole new course of action--where we go to school, what job we apply for, where we live, who we vote for. . .
3. Change moves in spirals, not circles.
At this point the analogy between Newton and dialectics runs out of steam. I think I would be stretching the point to argue that acceleration of an object in motion is analogous to negation of negation. But 2 out of 3 is not too bad.
It is worth noting that Newton's 2nd law implies the first and third law--i.e. If there is no force applied to an object, there is no acceleration, and the object remains in motion (or at rest). And the force applied to an object must overcome the reactions to that force, or again, there will be no change in motion.
And, yes, Einstein's laws of relativity show that Newton's laws don't apply in cases where the object is traveling near the speed of light. But that's a little beyond the scope of this essay.