A recently translated book by French theologian Reginald Garrigou-Lagrange, ‘Thomistic Common Sense,’ argues that modernity has made a lot of life’s basic questions more complicated than they need to be.

Common sense is a strange thing. It’s supposed to be a universal trait across all humanity – that’s why it’s called “common” – but ask any stranger on the street, and many will tell you it’s in short supply, whether among everyday Americans, politicians, and even among technocratic experts.

Consider commentary regarding COVID-19 and the Centers for Disease Control, a federal organization with a $6.5 billion budget employing almost 11,000 people. Double-masking against mutant forms of the coronavirus “just makes common sense,” Dr. Anthony Fauci told NBC’s “Today Show” in January.

“The CDC is being overly cautious in a way that defies common sense,” said CNN Medical Analyst Dr. Leana Wen in May, commenting on the CDC’s handling of the pandemic. More recently, Iowa Gov. Kim Reynolds in turn denounced the CDC’s recently revised face mask guidance for the fully vaccinated as “not grounded in reality or common sense.”

What is common sense? Is it simply a faux concept we employ to ridicule people we view as misguided or stupid? If it is lacking not only among American citizens writ large but also among respected, well-educated professionals, how can it be “common” at all?

Although few may know it, common sense derives from a particular philosophical thesis that has provoked controversy since antiquity. The ancient Greek philosopher Heraclitus believed all things are in a constant state of change or “becoming.”

Another ancient Greek, Parmenides, in contrast argued for the reality of eternal, unchanging being. Aristotle in turn argued for a sort of synthesis of the two, proposing that all of reality can be understood in regards to potency (what one has the potential to be) and act (the exercise of the fulfillment of that potential, i.e. change).

Apprehending Common Sense

What does that have to do with how we typically understand common sense — be it taking health precautions like washing your hands often and eating well, or professional prudence like making sure you have another job lined up before quitting your current one? More than you might think.

As Reginald Garrigou-Lagrange, O.P., argues in his Thomistic Common Sense: The Philosophy of Being and the Development of Doctrine — recently translated by Matthew K. Minerd — common sense is only coherent if it derives from a specifically Aristotelian-Thomistic understanding of being. That might sound esoteric, but the basic outline of Garrigou-Lagrange’s argument is not.

Humans, even children, apprehend the idea of being. They understand the principle of identity, that “every being is itself” — mommy and daddy are different; cookies are different (and better) than pureed peas. From that follows the principle of noncontradiction: Something cannot at be and not be what it is at the same time.

So does the principle of substance: That which is, is one and the same under its multiple and transitory manners of being. In other words, multiples are only intelligible in function of the one (those two things are different but both are “dog”), and what is transitory is intelligible only in function of what is permanent and identical (that cookie is gone, but “cookie” as an idea remains — thus “more!”).

As any parent knows, children also understand the principle of raison d’être or “reason for being”: Everything is intelligible, and everything has a purpose. Indeed, as Garrigou-Lagrange explains, “to deny this would be to identify that which is with that which is not.”

Consider a simple flower: Anthers hold pollen grains; stigmas trap and hold the pollen; petals attract pollinators; and sepals protect the developing bud. All serve a purpose that contributes to the life of the being that is a flower. If there was no raison d’être to these individual parts, there would be no flower.

There is still more we can apprehend via common sense. If things have purposes and ends, then we as rational beings can also conclude the first principle of practical reason: Namely, that the good must be done and evil avoided. This is so because “goodness is nothing other than the perfection of being.”

All beings desire to survive, and rational beings desire to thrive and excel. Thus we appreciate different species of good: the sensible or delightful good; the good that is useful to achieve an end; and the good that is most fitting. Finally, we understand ourselves as free because we can choose between different goods.

This might seem all fairly straightforward, but much of modern philosophy since the Enlightenment has rejected it. Immanuel Kant rejected raison d’être as entirely subjective because of his rejection of all knowledge originating in being. Rene Descartes — who authored the famous phrase cogito ergo sum — believed our intellect knows itself before it knows being. The pantheist Baruch Spinoza rejected free will because our wills are determined in some ways.

Obscuring Reality

Thus philosophy in our own day is understood not as something that clarifies reality, but obscures it. Writes Garrigou-Lagrange 100 years ago: “How many times, after leaving the courses of the Sorbonne, did the judgment of Saint Paul concerning the philosophers of his times come back to our own mind … ‘Claiming to be wise, they became fools, and exchanged the glory of the immortal God for images resembling mortal man.’”

Most Americans understandably look askance at philosophy as arcane nonsense, all the while drawing haphazardly from utilitarianism, materialism, moral relativism, and various other modern and postmodern systems, in order to make sense of life. Intellectual coherency matters little.

To all of this, Garrigou-Lagrange would retort: “Nothing is intelligible except in function of being.” In other words, inasmuch as any of us actually employ our common sense, we rely upon the same ideas articulated by Aristotle and his medieval interpreter Thomas Aquinas.

We may pretend there is no meaning in the cosmos, but if our plumber were to shrug his shoulders about a water leak because life has no purpose, we’d be less than thrilled. We may claim there’s no free will, but if our waiter brought us something different than what we had ordered — perhaps casually asserting that our choices are irrelevant — we’d protest and refuse to pay.

But if we expect others to practice common sense, we must be willing to do so ourselves, and accept the logical deductions that follow from its premises. This includes recognizing that our intellect and will, which abstract from the material, must necessarily be immaterial. That being so, that would mean our soul, which is the agent of our intellect and will, is also immaterial. And if the soul is immaterial, that means its ultimate object — a being that is the ultimate origin and perfection of being — must be too. Or, as God said to Moses, “I am who I am.”

Recovering our common sense, it appears, requires recovering a sense of the divine, as well. And that, one imagines, would likely affect how we view the often hysteric, frequently contradictory approaches to this pandemic.