You are right, basically anything can be viewed as a computation. Ray Kurzweil discusses this extensively in his book The Singularity is Near, building upon pre

You are right, basically anything can be viewed as a computation. Ray Kurzweil discusses this extensively in his book The Singularity is Near, building upon previous work by Edward Fredkin. > To appreciate the feasibility of computing with no energy and no heat, consider the computation that takes place in an ordinary rock. Although it may appear that nothing much is going on inside a rock, the approximately 1025 (ten trillion trillion) atoms in a kilogram of matter are actually extremely active. Despite the apparent solidity of the object, the atoms are all in motion, sharing electrons back and forth, changing particle spins, and generating rapidly moving electromagnetic fields. All of this activity represents computation, even if not very meaningfully organized. (From The Singularity is Near Chapter 3, The Limits of Computation)