One of the most unlikely philosophical bestsellers in recent decades was retired Princeton University professor Harry Frankfurt’s On Bullshit. Published in 2005, it remained on the New York Times best seller list for 27 weeks. It opens:

One of the most salient features of our culture is that there is so much bullshit. Everyone knows this. Each of us contributes his share. But we tend to take the situation for granted. Most people are rather confident of their ability to recognize bullshit and to avoid being taken in by it. So the phenomenon has not aroused much deliberate concern, or attracted much sustained inquiry. In consequence, we have no clear understanding of what bullshit is, why there is so much of it, or what functions it serves.

What is bullshit? Frankfurt distinguishes between lying and bullshitting. A liar knows that there is a difference between getting things wrong and getting them right—and opts for falsehood. A bullshitter, by contrast, believes that it is not possible to distinguish the false from the true. Yet this realization does not prevent him from making assertions about the way things are.

As portrayed in Plato’s dialogues, sophists such as Protagoras and Gorgias sought not the truth, but the power to persuade, to argue and win every time. Their most outspoken critic, Socrates, distinguished philosophy from sophistry, arguing that the philosopher seeks the truth about things. In a debate, like a boxing match, the end is to declare a winner and a loser. Dialogue, by contrast, aims to arrive at deeper understanding, an endeavor from which both parties can emerge enlightened.

Why is there so much bullshit? Frankfurt writes that “Bullshit is unavoidable whenever circumstances require someone to talk without knowing what he is talking about.” The bullshitter, he argues, has ceased trying to describe the way things really are and instead substitutes sincerity. Reality having ceased to provide a standard by which to evaluate statements, it is replaced by the speaker, who seeks merely to be true to himself. Man, as the sophist Protagoras argued, becomes the measure of all things.

For bullshit to thrive, in other words, people must be convinced that there is no objective truth. One indirect means of advancing such an argument is to convert all argument into what logicians call ad hominem attacks. Instead of engaging a point of view on its merits, one simply assails the individual who holds it, impugning his character or motives. Consider the source, the argument goes—if the advocate is flawed, then his positions must be flawed. Such attacks have become a regular feature of contemporary political discourse, often descending to the level of mere name-calling.

In my view, the ascendancy of bullshit can be explained in part by the changing media through which we have become accustomed to communicate. The 1858 U.S. Senatorial debates between Abraham Lincoln and Stephen Douglas famously lasted three hours and were reproduced in their entirety in the newspapers of the day. Today, by contrast, political discourse often takes the form of soundbites, and the most salient political medium seems to be Twitter. Where there were once melodies, now there are tweets.

The Canadian media theorist Marshall McLuhan foresaw such a situation when he coined the phrase, “The medium is the message.” As political discourse moves from print media such as newspapers to broadcast media such as television, what a candidate has to say can be quickly superseded by how a candidate looks. As discourse moves from television to Twitter, it can be further degraded into mere flamboyance. What matters is no longer speaking the truth but simply attracting and holding attention. Getting it right gives way to getting noticed.

This point was amplified by another media theorist, Neil Postman, who contended that television is a supremely visual medium that rejects ideas. In his 1985 book Amusing Ourselves to Death, Postman argued that “It is in the nature of the medium that it must suppress the content of ideas to accommodate the requirements of visual interest; that is to say, to accommodate the values of show business.” Recognizing that appealing to the emotions of the television audience is far more important than rational argument, bullshitters can quickly commandeer attention, a problem exacerbated by digital media such as Twitter.

Consider the experience of reading a Platonic dialogue such as the Protagoras. Socrates has no beef with Protagoras’ claim to be able to teach young men how to win arguments and manage their property. What he wants to know is whether Protagoras can teach them to be good. The question, in other words, is whether goodness is a form of knowledge and therefore learnable. If it is, then Protagoras is engaged in the worthiest form of life. But if he were leading such a life, why would he charge a fee for his teaching? The intrinsically most choice worthy should require no incentive.

Plato is inviting Protagoras, his interlocutors, and the dialogue’s readers to consider not why goodness might be useful but a more fundamental question—what goodness is. It is not a matter of simply producing a definition of goodness but exploring its nature, for if we can grasp what it is, then we will require no incentive for its pursuit. Protagoras and his heirs, however, turn out to care less about truth than the wealth and power that celebrity can bring.

For Socrates, this is a damning criticism, for the goal is not merely to command attention but to pursue wisdom. To lead a life grounded in falsehood, or at least to fail to put the truth above all else, is to subvert the higher to the lower—we end up living upside down. We must, says Socrates, “conduct our inquiry together in our own persons, making a trial of truth and ourselves.” The truth must be not only apprehended but also embodied, and someone whose life is grounded in falsehood cannot really be living. Where bullshit reigns, people are in chains.

To foster greater truth seeking and deeper devotion to goodness and wisdom for their own sake, we need heirs of Socrates who exemplify both such pursuits and their fruits—role models of the goodness-driven life in the arts, in the classroom, and yes, perhaps even in contemporary media. Without such teachers, we are consigned to continue along our path of descent, dumbing down not only the messages but the messengers, and making bullshitters of us all.