Molecular chemistry implementing reversible chemical bonds in molecules, and supramolecular chemistry, whose molecular components are held together by intermolecular interactions, may continuously change constitution by building block exchange. They define a Constitutional Dynamic Chemistry on both molecular and supramolecular levels. It takes advantage of dynamic constitutional diversity to allow for variation and selection in response to either internal or external factors to achieve adaptation, pointing to the emergence of adaptive chemistry. Lehn, J.-M., From supramolecular chemistry towards constitutional dynamic chemistry and adaptive chemistry, Chem. Soc. Rev. 2007, 36, 151. Lehn, J.-M., Perspectives in Chemistry – Steps towards Complex Matter, Angew. Chem. Int. Ed. 2013, 52, 2836.