Immunology's theories of cognition

Contemporary immunology has established its fundamental theory as a biological expression of personal identity, wherein the "immune self" is defended by the immune system. Protection of this agent putatively requires a cognitive capacity by which the self and the foreign are perceived and thereby discriminated; from such information, discernment of the environment is achieved and activation of pathways leading to an immune response may be initiated. This so-called cognitive paradigm embeds such functions as "perception," "recognition," "learning," and "memory" to characterize immune processes, but the conceptual character of such functions has meanings that vary with the particular theory adopted. When different formulations of cognition are considered, immunology's conceptual infrastructure shifts: Extensions of conventional psychological understanding of representational cognition based on a subject-object dichotomy support notions of immune agency; alternatively, formulations of perception that dispense with representations and attendant notions of agency reconfigure the predicate epistemology dominating current immune theory. Reviewing immunological literature of the past five decades, these two understandings of perception--representational and non-representational (considered here from ecological, enactivist, and autopoietic perspectives)--offer competing views of immune cognitive functions. These, in turn, provide competing philosophical understandings of immunology's conceptual foundations, which reflect parallel controversies dominating current debates in philosophy of mind and attendant discussions about personal identity.