Before the 19^th century, science was called natural philosophy or natural history. Since the ancient Greeks, the study of nature had been a branch of philosophy, a gentlemanly discussion of ideas by men who disdained to soil their hands with actual materials. What split science off from medieval philosophy was the use of experiment, careful observation, quantitative measurement with instruments, and what became known as scientific method, which meant testing ideas by hands-on experiment. Science became the application of technology to the study of nature. This in turn gave rise to further technology in a happy cycle involving the mutual interaction of mind and matter.

Philosophy literally means love of wisdom. In modern times it has instead largely come to mean love of sophistry. The secession of science from philosophy left the latter awkwardly bereft and defensive. One of the reasons why science emerged as distinct from philosophy is that medieval scholastic philosophy had been (as modern philosophy largely remains) mere talk about who said what about who said what. Science got down to brass tacks, focusing on the natural world, but at the cost of generality. Philosophy could trade on being more general in focus, if less verifiably factual. It could still deal with areas of thought not yet appropriated by scientific study, such as the nature of mind. And it could deal in a critical way with concepts developed within science—which became known as philosophy of science. Either way, the role of philosophy involved the ability to stand back to examine ideas for their logical consistency, meaning, tacit assumptions, and function within a broader context. The focus was no longer nature itself but thought about it and thought in general. Philosophy assumed the role of “going meta,” to critically examine any proposed idea or system from a viewpoint outside it. This meant examining a bigger picture, outside the terms and borders of the discipline concerned, and examining the relationships between disciplines. (Hence, metaphysics as a study beyond physics.) However, that was not the only response of philosophy to the scientific revolution.

Philosophy had long been closely associated with logic, one of its tools, which is also the basis of mathematics. Both logic and mathematics seemed to stand apart from nature as eternal verities, upstream of science. Galileo even wrote that mathematics is the language of the book of nature. So, even though science appropriated these as tools for the study of nature, and was strongly shaped by them, logic and math were never until recently questioned or considered the subject matter of scientific study. The increasing success of mathematical description in the physical sciences led to a general “physics envy,” whereby other sciences sought to emulate the quantifying example of physics. Sometimes this was effective and appropriate, but sometimes it led to pointless formalism, which was often the case in philosophy. Perhaps more than any other discipline, philosophy suffered from an inferiority complex in the shadow of its fruitful younger sibling. Philosophy could legitimize itself by looking scientific, or at least technical.

Certainly, all areas of human endeavor have become increasingly specialized over time. This is true even in philosophy, whose mandate remains, paradoxically, generalist in principle. Apart from the demand for rigor, the tendency to specialize may reflect the need for academics to remain employed by creating new problems to solve; to make their mark by staking out a unique territory in which to be expert; and to differentiate themselves from other thinkers through argument. Specialization, after all, is the art of knowing more and more about less and less, following the productive division of labor that characterizes civilization. On the other hand, specialization can lead to such fragmentation that thinkers in diverse intellectual realms are isolated from each other’s work. Worse, it can isolate a specialty from society at large. That can imply an enduring role for philosophers as generalists. They are positioned to stand back to integrate disparate concepts and areas of thought into a larger whole—to counterbalance specialization and interpret its products to a larger public. Yet, instead of rising to the occasion provided by specialization, philosophy more often succumbs its hazards.

Science differs from philosophy in having nature as its focus. The essential principle of scientific method is that disagreement is settled ultimately by experiment, which means by the natural world. That doesn’t mean that questions in science are definitively settled, much less that a final picture can ever be reached. The independent existence of the natural world probably means that nature is inexhaustible by thought, always presenting new surprises. Moreover, scientific experiments are increasingly complex, relying on tenuous evidence at the boundaries of perception. This means that scientific truth is increasingly a matter of statistical data, whose interpretation depends on assumptions that may not be explicit—until philosophers point them out. Nevertheless, there is progress in science. At the very least, theories become more refined, more encompassing, and quantitatively more accurate. That means that science is progressively more empowering for humanity, at least through technology.

Philosophy does not have nature as arbiter for its disputes, and little opportunity to contribute directly to technological empowerment. Quite the contrary, modern philosophers mostly quibble over contrived dilemmas of little interest or consequence to society. These are often scarcely more than make-work projects. The preoccupations and even titles of academic papers in philosophy are often expressed in terms that mock natural language. In the name of creating a precise vocabulary, their jargon establishes a realm of discourse impenetrable to outsiders—certainly to lay people and often enough even to other academics. More than an incidental by-product of useful specialization, abstruseness seems as much a ploy to justify existence within a caste and to perpetuate a self-contained scholastic world. If philosophical issues are by definition irresolvable, this at least keeps philosophers employed.

Philosophy began as rhetoric, which is the art of arguing convincingly. (Logic may have arisen as a rule-based means to reign in the extravagances of rhetoric.) Argument remains the hallmark of philosophy. Without nature to reign thought in, as in science, there is only logic and common sense as guides. Naturally, philosophers do attempt to present coherent reasoned arguments. But logic is only as good as the assumptions on which it is based. And these are wide open to disagreement. Philosophical argument does little more than hone disagreement and provide further opportunities to nit-pick. For the most part, philosophical argument promotes divergence, when its better use (“standing back”) is to arrive at convergence by getting to the bottom of things. That, however, would risk putting philosophers out of a job.

Philosophy resembles art more than science. Art, at least, serves a public beyond the coterie of artists themselves. Art too promotes divergence, and literature serves the multiplication of viewpoints we value as creative in our culture of individualism. Like artists, professional philosophers might find an esthetic satisfaction in presenting and examining arguments; they might revel in the opportunity to stand out as clever and original. However, philosophy tends to be less accessible to the general public than art. (Try to imagine a philosophy museum or gallery.) Professional philosophy has defined itself as an ivory-tower activity, and academic papers in philosophy tend to make dull reading, when comprehensible at all. That does not prevent individual philosophers from writing books of general and even topical interest. Sometimes these are eloquent, occasionally even best-sellers. Philosophers may do their best writing, and perhaps their best thinking, when addressing the rest of us instead of their fellows. After all, they were once advisors to rulers, providing a public service.

If philosophy is the art of splitting hairs, the metaphor generously conjures the image of an ideally sharp blade—the cutting edge of logic or incisive criticism. The other metaphor—of “nitpicking”—has less savory connotations but more favorable implications. Picking nits is a grooming activity of social animals, especially primates. It serves immediately to promote cleanliness (next to godliness, after all). More broadly, it serves to bond members of a group. We complain of it as a negative thing, an excessive attention to detail that distracts from the main issue. Yet its social function is actually to facilitate bonding. The metaphor puts the divisive aspect of philosophy in the context of a potentially unifying role.

That role can be fulfilled in felicitous ways, such as the mandate to stand back to see the larger picture, to find hidden connections and limiting assumptions, to “go meta.” It consists less in the skill to find fault with the arguments of others than to identify faulty thinking in the name of arriving at a truth that is the basis for agreement. Perhaps most philosophers would insist that is what they actually do. Perhaps finding truth can only be done by first scrutinizing arguments in detail and tearing them apart. However, that should never be an end in itself. As naïve as it might seem, reality—not arguments—should remain the focus of study in philosophy, as it is in science. Above all, specialization in philosophy should not distract from larger issues, but aim for them. Analysis should be part of a larger cycle that includes synthesis. Philosophy should be true to its role of seeking the largest perspective and bringing the most important things into clear focus. It should again be a public service, to an informed society if no longer to kings.