the problem of scientific knowledge must be posed in terms of obstacles.
– Gaston Bachelard, The Formation of the Scientific Mind

We take from Gaston Bachelard the notion of the obstacle, which is said to lay ‘at the very heart of the act of cognition’. Perhaps more significant was his notion of the epistemological obstacle which obscures the vector of abstraction peculiar to thought. This notion had a profound effect on the trajectory of French Rationalism, particularly in the work of Louis Althusser, where such obstacles were submitted to ‘management’ through the manipulative techniques of inquiry and the engineering of an ‘apparatus of theoretical vision’. The effect of this management could properly be called deconstruction. Its function was related to the uncovering of objects whose visibility was foreclosed by the existing visibilities within a theoretical terrain. The epistemological obstacle is thus closely related to the establishment of new theoretical terrain and therefore related to the logics of frontiers, models, and horizons. While Bachelard may have placed the epistemological obstacle in specific relation to scientific practice, we see it as having consequences for other domains and modes of thought, particularly when this concerns moments of social or conceptual transformation. In his chapter on the epistemological obstacle in The Formation of the Scientific Mind, Bachelard himself will say that

Critical moments in the growth of thought involve in fact a total reorganisation of the system of knowledge. The well-drilled mind must then be remade. It changes species. It sets itself against the previous species through a decisive function. Through the mental revolutions that scientific invention requires, humankind becomes a mutating species, or to put it better still, a species that needs to mutate, that suffers if it does not change.