Fleeting objects, enduring information

Information can only be defined as an equivalence class of sequences with respect to alphabet changes and encodings, hence it is an abstract entity. However, a sequence is necessarily borne by a physical support. Information thus appears as a bridge between the abstract and the concrete. In the living world, the information borne by genomes acts on matter by instructing the assembly of objects. Physical perturbations degrade the supports, hence the sequences they bear, but the information they represent can be almost indefinitely conserved provided they are endowed with error-correcting codes as powerful as to enable their regeneration, and regenerated frequently enough. Codes made of nested components which successively originated over the ages account for the conservation of the oldest parts of the genomes. The component codes are `soft´, meaning that they result from any kind of non-mathematical constraint, e.g., physical-chemical or linguistic. The genomic information instructs the assembly of living structures by the agency of interwoven semantic feedback loops which lock themselves because the synthetized enzymes catalyse their own assembly.