Thing Knowledge: A Philosophy of Scientific Instruments (review)

An eighteenth-century orrery, the first cyclotron, and a grating spectrometer are unlikely to occupy a lab shelf together. Yet each involves physical understanding—not only of planetary motion, particle beams, or spectral lines, but also of whatever else attends its use, design, and makeup. They not only provide new evidence, they embody knowledge of a kind that Davis Baird terms "thing knowledge." Baird coherently develops its various forms, its emergence as equal counterpart to text-based theoretical knowledge, and its impact on knowledge-making today and for the future.

Books contain knowledge, but how can a thing? Orrery clockwork demonstrates the relative orbits of planets and performs rough calculations. It models knowledge, accessing visual, tactile, and spatial dimensions of understanding. Model knowledge is adjunct to theory, but not theory itself. The homemade cyclotron constructed by E. O. Lawrence's student in 1930 applied voltage pulses to ions circulating within. High currents observed at certain pulse rates showed a new resonance effect. Such an instrument produces novel phenomena that appear only under its operating conditions, and run better as the apparatus is improved and the operator's experience grows. Baird categorizes these instruments together, for exhibiting "working knowledge." A spectrometer's grating disperses incident light, sending each "color" to a unique position where its intensity is detected and electronically compared to a known light source. Measuring instruments like this function by combining model knowledge, as encoded in the spectrometer's scale of spectral dispersion, with working knowledge, as evolved in dispersing and detecting light. Orrery, cyclotron, and spectrometer exemplify three forms of thing knowledge, each involving a complexity of materials and experience that cannot be reduced to words alone.

But putting something into words—having a theory—was considered requisite for advancing science. That assumption fails with twentieth-century science, where instrumentation, with no new theory, transformed analytic chemistry. Qualitative procedures on an unknown reactant's products gave way to direct quantitative determinations of properties and identity. Baird knows this particular story from the inside; his father's company innovated several key instruments. Personnel records and employee interviews have enabled him to trace these emergent technologies along with what kept participants going. Baird's dad expressed that spirit when he said: "I want to get my hands on things again" (p. 147).

Creations of handiwork are shown true—or not—in their running, like a well-balanced bicycle wheel. Hands learn while materials teach, yet this learning rarely gains our fullest respect. Countering the tendency to equate knowledge with ideas, Baird describes lessons inherent in things. A perfect screw cannot be made; everything material is flawed—and therein lies the interest in it. To find out whether some material will suffice for making an instrument, we must mess with the stuff directly; this behavior cannot be otherwise predicted. But once an instrument operates with minimal fuss, these same properties recede into the background. It becomes a black box whose users need not understand the thing knowledge by which it runs.

Baird's arguments—that things bear knowledge that is only gained firsthand—will delight many people, including museum curators and shop instructors. Yet thing knowledge remains elusive when artifacts themselves preserve no clues about past function, or when learning is confined to symbolic exercises. Thing knowledge depends on experience and is endangered whenever experience wanes, an increasing risk in our media-saturated world.

While Baird's thorough research honors overlooked yet substantial contributions of thing knowledge, he also perceives a similarly ignored underside. Instrumentation has taken over tasks formerly dependent on human judgment. For example, standardized testing replaces teachers' grading with machine scoring. This has implications beyond simply lowering costs; as "objectivity" becomes synonymous with automation, our human capacity for evaluation is devalued. But this exploitation of instrumentation without addressing its hidden human toll portends yet deeper peril. When things bear knowledge, and things cost money, knowledge becomes a commodity. When knowledge is sold for profit, secrecy confers advantage and all interpersonal...