Knows that things have properties (e.g., magnetism, conductivity, density, solubility) that can be used to tell them apart and to find out which of them are alike.
Mixing and Stirring
Combining two fluids (confluence of two rivers, Mediterranean water spilling over the straits of Gibraltar into the Atlantic) involves two processes: (1) stirring -- stretching of the bulk fluid, and (2) mixing -- exchange of materials on the molecular level (diffusion).
