Those who work in some educational institutions will find this question bizarre, because the assumption that medical activity is scientific activity has long been in place.
The alternative is perhaps to view medicine as a skill, a craft, an art. Lying at the core of the question is, of course, the definition of ‘science.’
Siddhartha Mukherjee begins with a somewhat belabored comparison of ‘science’ and ‘scientific,’ but makes the important point that merely being technological, or applying technology, does not by itself qualify an activity as science.
Is medicine a science? If, by science, we are referring to the spectacular technological innovations of the past decades, then without doubt medicine qualifies. But technological innovations do not define a science; they merely prove that medicine is scientific - i.e., therapeutic interventions are based on the rational precepts of pathophysiology.
One feature of science, he argues, is that it has laws, or identifies lawlike regularities. Mathematics and some branches of physics are here paradigmatic.
Sciences have laws — statements of truth based on repeated experimental observations that describe some universal or generalizable attributes of nature. Physics is replete with such laws. Some are powerful and general, such as the law of gravitation, which describes the force of attraction between two bodies with mass anywhere in the universe. Others apply to specific conditions, such as Ohm’s law, which only holds true for certain kinds of electrical circuits. In every case, however, a law distills a relationship between observable phenomena that remains true across multiple circumstances and multiple conditions. Laws are rules that nature must live by.
Mathematics and physics are abstract and conceptual. As sciences become more concrete - more tied to empirical observation - their ‘scientificness’ decreases.
Imagine, if you will, the differences you might encounter in scientific texts over a fifty-year span of time. If you looked at a chemistry textbook published today, and you find a precise measurement of the atomic mass of an element, say Osmium, and it was so precise that it went to ten or twenty or even thirty decimal places, then you would have the most precise empirical data available.
But continue to imagine that fifty years later, another chemistry textbook was published. It might also list the atomic mass for the same isotope of Osmium, but quite conceivably, at the very last digit of the ten or twenty or thirty decimal places, there might be a difference between the later book and the earlier book.
There might have been some revision based on more careful experiments, based on new instrumentation, based on new understandings of how to get the most accurate value.
Far from being unusual, such revision of values is in fact part of empirical or observational science.
By contrast, imagine two mathematics books published fifty years apart: there will be no difference, no revision, in the quadratic formula or the Pythagorean theorem.
This difference, in our little imaginary thought experiment, between mathematics and chemistry, gives us an insight into laws, lawlike correlations, and science - although this does not yet fully explain what it is to be a science.
There are fewer laws in chemistry. Biology is the most lawless of the three basic sciences: there are few rules to begin with, and even fewer rules that are universal. Living creatures must, of course, obey the fundamental rules of physics and chemistry, but life often exists on the margins and in the interstices of these laws, bending them to their near-breaking limit. Even the elephant cannot violate the laws of thermodynamics — although its trunk, surely, must rank as one of the most peculiar means to move matter using energy.
Surely chemistry and biology - along with the less abstract and more empirical, applied, and experimental aspects of physics - are sciences, even if they are a bit fuzzy around the edges.
We are tempted to say, “They are sciences because they have laws.” But we must first ask if everything that is a science has laws, and then we must ask, if everything that has laws is a science.
Does medicine have laws? Siddhartha Mukherjee asks this question, because it will go a long way toward deciding whether medicine is a science.
Medicine has general rules and practices and guidelines, but does it have laws?
But does the “youngest science” have laws? It seems like an odd preoccupation now, but I spent much of my medical residency seeking the laws of medicine. The criteria were simple: a “law” had to distill some universal guiding principle of medicine into a statement of truth. The law could not be borrowed from biology or chemistry; it had to be specific to the practice of medicine.
If medicine does have laws, would they be in some essential way different than the laws of the various sciences? Medicine is applied: the essence of medicine is to do something, while sciences are essentially about knowing something.
To phrase it another way, do applied sciences have their own laws, distinct from pure sciences? Siddhartha Mukherjee writes:
I was genuinely interested in rules, or principles, that applied to the practice of medicine at large.
Consider for titles of well-known journals like Pure and Applied Mathematics. Consider that branch of physics which studies electromagnetism compared with the profession of being an electrician. Consider biology and medicine.
In each of these pairs of pure and applied science, do we find that the applied version of the science has its own laws, or does it merely help itself to the laws of its pure sibling?
Of course, these would not be laws like those of physics or chemistry. If medicine is a science at all, it is a much softer science. There is gravity in medicine, although it cannot be captured by Newton’s equations. There is a half-life of grief, even if there is no instrument designed to measure it. The laws of medicine would not be described through equations, constants, or numbers. My search for the laws was not an attempt to codify or reduce the discipline into grand universals. Rather, I imagined them as guiding rules that a young doctor might teach himself as he navigates a profession that seems, at first glance, overwhelmingly unnavigable. The project began lightly — but it eventually produced some of the most serious thinking that I have ever done around the basic tenets of my discipline.
Siddhartha Mukherjee introduces the distinction between ‘science’ and ‘soft science,’ and even then wonders “if medicine is a science at all.” Crucially, he notes the lack of quantifiability in anything which might present itself as a ‘law of medicine.’
Although modern medicine is conducted with endless quantifications and measurements, the core of practice, medical decision-making, is non-numerical. There is some skill of judgment, of non-quantified reasoning, which the medical practitioner has.
We will leave the question unanswered, whether medicine is a science, but the consideration of the question gives opportunities for insights nonetheless.
