Well, I must admit Barad was one of those I was thinking of when I asked 
whether we could also see an 'arbitrary closure' (what, following Barad, 
we might think of in terms of a 'cut'?) at work in the way the 
intellectual theoretical work that is most acceptable and feted today  
is often quite materialist in tenor.

I guess not knowing, for me, would not exclude knowing. While it is of 
course necessary to know as much and as best as we can, not knowing is 
something that can't be removed from (or simply contrasted to) the 
process of knowing. But this is certainly something Barad can help us to 
understand and think about:

'Knowing is not a bounded or closed practice but an ongoing performance 
of the world.' (Meeting the Universe Halfway: Quantum Physics and the 
Entanglement of Matter and Meaning, p.149)

Or, for a much longer extract from the same book that more clearly 
relates to Helen's reference to the process of 'diffraction' (as well as 
Bauwens' emphasis on the possibiity of creating a world based on a new 
logic he associates with peer-to-peer networks of production):

'First and foremost, as Haraway suggests, a diffractive methodology is a
critical practice for making a difference in the world. It is a 
commitment to
understanding which differences matter, how they matter, and for whom. It
is a critical practice of engagement, not a distance-learning practice 
of reflecting
from afar. The agential realist approach that I offer eschews 
and advances a performative understanding of technoscientific
and other naturalcultural practices, including different kinds
of knowledge-making practices. According to agential realism, knowing,
thinking, measuring, theorizing, and observing are material practices of
intra-acting within and as part of the world. What do we learn by engaging
in such practices? We do not uncover preexisting facts about independently
existing things as they exist frozen in time like little statues 
positioned in the
world. Rather, we learn about phenomena-about specific material 
of the world's becoming. The point is not simply to put the observer
or knower back in the world (as if the world were a container and we needed
merely to acknowledge our situatedness in it) but to understand and take
account of the fact that we too are part of the world's differential 
And furthermore, the point is not merely that knowledge practices have
material consequences but that practices of knowing are specific 
material engagements
that participate in (re)configuring the world. Which practices we enact 
in both senses of the word. Making knowledge is not simply about
making facts but about making worlds, or rather, it is about making specific
worldly configurations-not in the sense of making them up ex nihilo, or out
of language, beliefs, or ideas, but in the sense of materially engaging 
as part
of the world in giving it specific material form. And yet the fact that 
we make
knowledge not from outside but as part of the world does not mean that
knowledge is necessarily subjective (a notion that already presumes the
preexisting distinction between object and subject that feeds 
thinking). At the same time, objectivity cannot be about producing
undistorted representations from afar; rather, objectivity is about 
being accountable
to the specific materializations of which we are a part. And this
requires a methodology that is attentive to, and responsive/responsible to,
the specificity of material entanglements in their agential becoming. The
physical phenomenon of diffraction makes manifest the extraordinary 
of the world.'
(Meeting the Universe Halfway: Quantum Physics and the Entanglement of 
Matter and Meaning, p. 90-91)

Gary Hall
Research Professor of Media and Performing Arts
Director of the Centre for Disruptive Media
School of Art and Design, Coventry University
Co-editor of Culture Machine
Co-founder of the Open Humanities Press