Parasite

A parasite is a specific kind of predator, distinguished by position rather than by appetite. Where an ordinary predator takes from a source, a parasite sits between two sources and takes from what passes between them, which is why interception is the operative word. The mechanism accounts for the characteristic exhaustion. Interception allows the parasite not only to take anima from an interaction but to extract more energy than is required to complete it, which is why interactions with predatory individuals or institutions are so tiring out of proportion to what is being transacted. Three harms follow from one action. The conduits are exhausted, the initiator receives no reward and the interaction that should have balanced does not. Parasitic relationships are therefore not merely one-sided but corrosive of the connection itself, since the flow is being intercepted by force rather than simply going unreciprocated. Marsh treats the condition as produced rather than chosen. A dependence on secondary anima causes people to become parasites, draining life from others by parasiting off interactions, which places the behaviour downstream of blocked primary conduits. At scale the parasites become the reflectors and enablers of exploitative power structures, since a structure encouraging them to welcome the misery of the negative image is a structure supplying what they need. This is also the shape of civilization in the framework, a vast network of interception points where whoever holds a point parasites off the transfers.

Parasitism in biology is a relationship in which one organism benefits at another's expense without necessarily killing it, and the metaphor has a long and often ugly political history, having been used to dehumanize groups before violence against them. Economics has rent-seeking, which describes value extracted through position rather than production and is the closest technical parallel to Marsh's interception. Michel Serres wrote a philosophical treatment of the parasite as the third party in any exchange. Marsh's usage is structural and role-based rather than applied to populations, and its distinctive element is the claim that the position produces the behaviour, which means the remedy is removing interception points rather than removing people.