“When describing solids, one may ignore time altogether; in describing fluids, to leave time out of account would be a grievous mistake. Descriptions of fluids are all snapshots, and they need a date at the bottom of the picture.
Fluids travel easily. They ‘flow’, ‘spill’, ‘run out’, ‘splash’, ‘pour over’, ‘leak’, ‘flood’, ‘spray’, ‘drip’, ‘seep’, ‘ooze’; unlike solids, they are not easily stopped – they pass around some obstacles, dissolve some others and bore or soak their way through others still. From the meeting with solids they emerge unscathed, while the solids they have met, if they stay solid, are changed – get moist or drenched.
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These are reasons to consider ‘fluidity’ or ‘liquidity’ as fitting metaphors when we wish to grasp the nature of the present, in many ways novel, phase in the history of modernity.”