3
1.1.1 Is measurement necessarily physical?
Thomas S. Kuhn (1961: p. 161) once observed that
at the University of Chicago, the facade of the Social Science Research Building bears Lord
Kelvin’s famous dictum: “when you cannot measure, your knowledge is of a meagre and
unsatisfactory kind”. Would that statement be there if it had been written not by a physicist,
but by a sociologist, political scientist, or economist? Or again, would terms like “meter
reading” and “yardstick” recur so frequently in contemporary discussions of epistemology
and scientific method were it not for the prestige of modern physical science and the fact
that measurement so obviously bulks large in its research?
We think it is hard to dispute that, for most, the paragon of measurement is physical
measurement. For some, this might even be the end of the conversation: measurement is necessarily of physical quantities, and thus anything called “measurement”
in the human sciences is either ultimately of something physical or at best a metaphorical application of the concept of measurement to something that is in fact not
measurement. And indeed, there is some historical weight to this argument: for
much of the history of human civilization, measurement was associated with a relatively small number of spatiotemporal properties, such as length, mass, and time
duration, and more recently force, temperature, and electric charge. As scientific
understanding of the physical world has advanced, these properties have become
increasingly understood as mutually interdependent, via physical laws (such as
Newton’s second law of motion, which posits that force is the product of mass and
acceleration); when values are attributed to physical properties, such laws can be
used for inferential purposes by operating mathematically on the available values by
means of the relevant laws. Reasoning about the physical world in this way proved
so successful that it was the common ground upon which new branches of physics
were created in the eighteenth and nineteenth centuries, in particular thermodynamics and electromagnetism, the development of each of which involved the discovery
of their own sets of properties and laws connecting them. And, of course, such scientific advances led to technological changes, which in turn triggered further scientific advances, as well as changes in society at large.
This positive feedback loop would not have been possible without effective tools
for obtaining information about the relevant properties. This is, of course, the role
played by measurement; as Norman Campbell effectively summarized, “the object
of measurement is to enable the powerful weapon of mathematical analysis to be
applied to the subject matter of science” (1920: p. 267).
3
Measurement is thus a
critical component of the scientific paradigm of the physical sciences, and has been
integral to its success.
Again, given this, it is perhaps unsurprising that other scientific fields and areas
of human activity have increasingly incorporated measurement-related concepts
3 This position seems to be broadly accepted in the human sciences as well; for example, as put by
Warren Torgerson, “measurement enables the tool of mathematics to be applied to science” (1958:
p. 1).
1.1 Why we wrote this book
1.1.1 Is measurement necessarily physical?
Thomas S. Kuhn (1961: p. 161) once observed that
at the University of Chicago, the facade of the Social Science Research Building bears Lord
Kelvin’s famous dictum: “when you cannot measure, your knowledge is of a meagre and
unsatisfactory kind”. Would that statement be there if it had been written not by a physicist,
but by a sociologist, political scientist, or economist? Or again, would terms like “meter
reading” and “yardstick” recur so frequently in contemporary discussions of epistemology
and scientific method were it not for the prestige of modern physical science and the fact
that measurement so obviously bulks large in its research?
We think it is hard to dispute that, for most, the paragon of measurement is physical
measurement. For some, this might even be the end of the conversation: measurement is necessarily of physical quantities, and thus anything called “measurement”
in the human sciences is either ultimately of something physical or at best a metaphorical application of the concept of measurement to something that is in fact not
measurement. And indeed, there is some historical weight to this argument: for
much of the history of human civilization, measurement was associated with a relatively small number of spatiotemporal properties, such as length, mass, and time
duration, and more recently force, temperature, and electric charge. As scientific
understanding of the physical world has advanced, these properties have become
increasingly understood as mutually interdependent, via physical laws (such as
Newton’s second law of motion, which posits that force is the product of mass and
acceleration); when values are attributed to physical properties, such laws can be
used for inferential purposes by operating mathematically on the available values by
means of the relevant laws. Reasoning about the physical world in this way proved
so successful that it was the common ground upon which new branches of physics
were created in the eighteenth and nineteenth centuries, in particular thermodynamics and electromagnetism, the development of each of which involved the discovery
of their own sets of properties and laws connecting them. And, of course, such scientific advances led to technological changes, which in turn triggered further scientific advances, as well as changes in society at large.
This positive feedback loop would not have been possible without effective tools
for obtaining information about the relevant properties. This is, of course, the role
played by measurement; as Norman Campbell effectively summarized, “the object
of measurement is to enable the powerful weapon of mathematical analysis to be
applied to the subject matter of science” (1920: p. 267).
3
Measurement is thus a
critical component of the scientific paradigm of the physical sciences, and has been
integral to its success.
Again, given this, it is perhaps unsurprising that other scientific fields and areas
of human activity have increasingly incorporated measurement-related concepts
3 This position seems to be broadly accepted in the human sciences as well; for example, as put by
Warren Torgerson, “measurement enables the tool of mathematics to be applied to science” (1958:
p. 1).
1.1 Why we wrote this book