Extensionism holds that all objects and events extend indefinitely through time and space. Because of constraints inherent in human (and perhaps animal) perceptual apparatus we tend to regard all objects in the world as coherent and discrete, a limitation Professor Robert Pepperell considers to be caused, in part, by "the coersive effects of time". In the Postscript to his book The Posthuman Condition, Robert Pepperell continues:
[E]xtensionism recognises the co-presence of opposites (such as a world that is both full of distinctions and devoid of distinctions, or an object that is more than one thing at the same time) without negating or resolving them...
In this regard, extensionism bears a resemblance to the notion of the quasi-object put forward by Michel Serres and furthered by Bruno Latour in his conception of 'Hybrids'.