Science versus Engineering

Science and engineering are closely related fields, to the point where people often confuse engineering for science. To put it simply, the telos of science is to push the boundary between the known and unknown, by producing theories that can be used to both predict and explain natural phenomena. On the other hand, the engineering method works at this boundary, producing heuristics that can be used to achieve practical ends. The job of an engineer is then "solving problems using rules of thumb that cause the best change in a poorly understood situation using available resources"^[1] Like scientists, engineers produce knowledge, however this knowledge is in the form of heuristics that work well enough in certain cases, but may be completely untrue at base. In this sense both science and engineering make predictions: science makes predictions in order to demonstrate explanations of nature, whereas engineers make predictions that are good enough to control nature. Engineering is purely instrumental, whereas science is trying to get at something deeper: namely, the truth.

It is of course the case that, for most people engaged in scientific enterprise, truthseeking is not an end in itself.¹ The truth is sought as a means to an end: namely, control. This is apparent as early as 1627 when one of the pioneers of the scientific method, Francis Bacon, published New Atlantis, the first scientific utopia. Historian of science Richard Westfall describes it:

In the New Atlantis [...] Bacon described Salomon's House, an organization devoted to "enlarging the bounds of Human Empire, to the effecting of all things possible." Nearly all of the research he described in Salomon's House was practical-improved orchards, improved breeds of animals, improved medicine. Bacon himself believed that practical results derive only from true theory, and he was not in any way opposed to what we call pure research. Nevertheless, the description of Salomon's House gives an accurate account of his ultimate goal. The purpose of knowledge is the relief of man's estate, the comfort and convenience of human life.^[2]

We might then ask, to what extent does engineering depend on science? Since engineering works at the boundary between the known and unknown, as sciences pushes back this boundary it increases the scope of problems which can be addressed by engineering. The development and formalization of chemistry eventually lead to chemical engineering; the development of molecular biology eventually lead to genetic engineering. Science also helps to constrain the search space in which engineering acts by ruling out certain approaches or objectives. For instance, the science of thermodynamics rules out the existence of perpetual motion machines, and the science of electromagnetism constrained approaches in the development of more efficient electric motors. It should also be noted that when scientific theories are wrong they can also serve to limit advancement in engineering. For instance, prior to the discovery of high-temperature superconductors in the 1980s such materials were thought to be impossible, which limited research interest and funding. Similarly, the first Invar alloy (a metal exhibiting near-zero thermal expansion) was discovered in 1895, contradicting then-modern theories of metallurgy.^[3] Since engineering operates on the boundary of scientific knowledge, it is often the case that an engineering discovery will precipitate the development of science in an area that now calls out for explanation.

Since I have characterized engineering as lying on the boundary of scientific knowledge, it is reasonable to ask whether a 'solved problem' then ceases to be engineering. When we consider the most basic objects in engineering practice, like gears, beams, or simple circuits, our knowledge is sufficiently complete to be so as to be considered a solved science. On the other hand, the building of a complex construct like an engine, a bridge, or a computer chip always presents as-yet unseen challenges which must be handled by the engineer. For instance, humans have been building bridges for thousands of years, and they may be considered as close to a solved problem as exists in civil engineering. Nonetheless, every new bridge that is built requires solving a complex optimization problem taking into account, among other things, the desired use cases, local geological conditions, the possibility of extreme weather events, and the budget and materials available for construction. Thus, while there may be a relatively complete scientific account of the available construction materials and local geology, the specific problem of building a particular bridge represents a novel case requiring the use of the engineering method, applying (or developing) useful heuristics.

A final, but important, distinction between science and engineering is that since engineering does not put forward explanatory theories, it is not falsifiable. Heuristics cannot be falsified, they simply cease to be useful. Therefore, unlike scientific theories which may in time be falsified and superseded, engineering heuristics simply become outdated as materials or methods change.

It is important to make the distinction between science and engineering because the fields are based on different teleological, methodological, and ontological bases. This distinction is important to observe because, as Popper writes in Conjectures and Refutations^[4] and I have written elsewhere, to disregard it vitiates the true explanatory power that accrues to science but not to engineering. It is especially pertinent today, when instrumentalism is the dominant philosophy of science (as it was even when Popper was writing) - a trend which seems to be gaining momentum with modern data-driven research methods.

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References:

1. Hammack, B. [The Things We Make]. (2023, May 9). Controlling Turbulence and Evolution: How Engineers Overcome Uncertainty [Video]. YouTube.

2. Westfall, R. S. (1977). The Construction of Modern Science: Mechanisms and Mechanics. United Kingdom: Cambridge University Press. p. 118

3. Rancourt, D. (2011, January 5). Activist Teacher: On the False Science of a Fundamental Basis for Progress. Activist Teacher. http://activistteacher.blogspot.com/2011/01/on-false-science-of-fundamental-basis.html

4. Popper, K. R. (1968). Conjectures and Refutations: The Growth of Scientific Knowledge (Chapter 3: Three Views Concerning Human Knowledge). Harper & Row.

1. Although I would argue that without this most fundamental orientation, true science cannot exist.