Against the familiar periodic table of neatly-defined elements the human body presents a multitude of non-specific tissues, what surgeon Roger Kneebone called “the bubblewrap of the organs”. It’s shocking to see how much of this ambiguous stuff exists inside us. Far from being the divine design of a crafty God, the human body is a mess, exhibiting sufficient pattern to be operated on but always convoluted enough to make the surgery difficult. This variety in tissues is reflected by variety in the emotions. No two people respond to anything the same way, but no two people’s emotions are different either. To respond to materials is to be in a state that defies orderliness and messiness together. It’s not a matter of either rational interaction or emotional experience or a struggle between one and the other, but always an “intersection”, a coming together of hands, emotions, senses, instruments, materials, intellect, place, scale, people, past, future and context, in which there is enough predictability to get on with the job but enough complexity to always create surprises. Sometimes these intersections are choreographed and sometimes they aren’t. Some are marked out in time, “the surgical operation” and others aren’t. Out of all of them come fear, arousal, enthusiasm, panic, delight, all integrated into a continuous interaction of performances, gestures, engagements with others, emerging rapidly. Crude heavy intersections, cutting bone with a saw, prompt different emotions and performances compared to light and fine ones, paring tissue with the finest scalpel. Surgery is not about supressing emotions, and the same can presumably be said of doing an experiment. Emotions have to be directed, some encouraged, others supressed, some accepted and acted upon, others ignored, the volume turned up sometimes, or turned down. Emotions are also social, emerging in the interactions of people and things, mediated by instruments and techniques shared across many pairs of hands. Metaphors also bridge experiences, as every person becomes a thing, and things are animated into life. People are like knives and tools that fix, heal, and remedy wounded bodies. Objects are inviting, approachable, persuadable, like people. The session taught me that if you delve into a surgical operation, it’s not just a clinical procedure, but a rapid-fire choreography of many tangible and intangible things.