I came across a succinct and probing summary of Michel de Certeau's ideas about strategies versus tactics in Tim Cresswell's On The Move: Mobility in the Modern Western World.  This comparison—and the affirmation of  the tactical—is referenced so often by artists, but usually without sufficient explanation as to why.

A long time ago I pointed to Mitchell Whitelaw's claim for the "non-industrial latitude" that artists enjoy when they stake claims to technology, media, data as their own. Deploying this latitude gives birth to tactics:  arts and design practices that defile, invert, or re-shape technologies from their ordinary functional uses. Practices that estrange us from the ordinary and force us to re-read technologies *as* culture. De Certeau, in 1984, anticipates the hacking impulse with revealing exactitude:

"Michel de Certeau, in The Practice of Everyday Life, enjoys the nomad metaphor. For him, power is about territory and boundaries—asserting what he calls a 'proper place.' The weapons of the strong are strategies—classification, mapping, delineation, division. The strong depend on the certainty of mapping. The weak, on the other hand, are left with furtive movement to contest the territorialization of urban space. The cunning of the nomad allows pedestrians to take short cuts, to tell stories through the routes they choose. These tactics refuse the neat divisions and classification of the powerful and, in doing so, critique the spatialization of domination. Thus, the ordinary activities of everyday life, such as walking in the city, become acts of heroic everyday resistance. The nomad is the hero(ine).

Tactics do not 'obey the laws of the place, for they are not defined or identified by it.' The tactic never creates or relies upon the existence of some place for its identity and power. The tactic is consigned to using the space of the powerful in cunning ways. The tactics of the weak are a form of consumption—never producing 'proper places' but always using and manipulating places produced by others. The world of production is thus confronted with 'an entirely different kind of production, called 'consumption,' which is marked by 'ruses,' fragmentation,' 'poaching,' and its 'quasi-invisibility'—it shows itself not in its own products...but in the art of using those imposed upon it.'

Thus the tactic is the ruse of the weak—the mobile drifting through the rationalized spaces of power. The tactic is a nomadic art—an art that will 'circulate, come and go, overflow and drift over an imposed terrain like the snowy waves of the sea slipping in and among the rocks and defiles of an established order.'"

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