The complex behavior of microparticles in a solution calls for different theoretical backgrounds. Here, we follow the line of two, recently developed theories on individuality, on the one hand, and conformational transitions of macromolecules in a solution, on the other. Given as separate theories, the two models may raise certain controversy in respect to their mutual consistency. Needless to say, their mutual consistency is necessary for the validity of the theories both in a general context as well as in search for a unified physico/chemical picture concerning the microparticles in a solution dynamics. We point out the consistency of these theories based on the definition of a molecule through its constituent subsystems (e.g. the center-of-mass and the “conformation” subsystems).