The accident, in Virilio's philosophy, is the negative potentiality inherent in every technological system. If the history of technoscientifi c innovation is conventionally understood as a progressive lineage, in which human capacities are incrementally augmented, enhanced and extended, then Virilio is determined to highlight the fact that every such advance necessarily brings into existence, as its ineradicable shadow, new risks, dangers and threats. As he puts it in conversation with Sylvere Lotringer in Pure War (2008):

Every technology produces, provokes, programs a specifi c accident. For example: when they invented the railroad, what did they invent? An object that allowed you to go fast, which allowed you to progress – a vision à la Jules Verne, positivism, evolutionism. But at the same time they invented the railway catastrophe. (PW, 46)

The accident, then, is central to Virilio's sceptical approach to technology. The roots of Virilio's notion of the accident lie in the philosophy of Aristotle. Whereas in Aristotelian metaphysics, however, ideas of the accident concern that which is secondary, relative, contingent or – precisely – accidental, in Virilio's ontology the potential for the accident is a necessary and essential property of any object or process. Similarly, Virilio fully mobilises the term's connotation of a destructive malfunctioning – a malfunctioning that is also, at the same time, the realisation of the phenomenon's true character:

The word accident, derived from the Latin accidens, signals the unanticipated, that which unexpectedly befalls the mechanism, system, or product, its surprise failure or destruction. As if the ‘failure’ were not programmed into the product from the moment of its production or implementation. (Virilio 1993 [1982]: 211–12; emphases in original)