The concept of knowledge and truth both, at least in the modern era, appear to be fairly straightforward; however, when one dives deeper the line between the truth and what the Academicians would call ‘truth-like’ blur. In modern society, there is a general consensus that everyone is on the path towards truth, even if they take another route. We depend on probabilities and are hesitant to say whether something is true or not, mostly in fear of being wrong. In Against the Academicians and On the Teacher, Augustine shows that this way of living is illogical, as there is a singular truth - namely God - and this path of truth leads to greater knowledge. 

When Saint Augustine writes Against the Academicians in 386 AD, he was a recent convert to Christianity and had briefly been involved in the academic skeptic movement before his conversion. The Academicians, or academic skeptics, were convinced that knowledge was unattainable and that truth did not exist, as the human senses could not be trusted because they were of the body and therefore prone to misperceptions. Their main fear was that of assenting to an incorrect position as it was worse to be held in error than just to hold plausibility. Augustine writes his work mainly to convince his friend Romananius to convert from Manichaeism to philosophy but also partly to stop the spread of the falsehoods that were being spread by the Academicians. In Against the Academicians, Augustine disproved their fundamental teachings using nothing more than logic and reason, ultimately proving that knowledge can be found and that truth does exist. 

On the Teacher, written in 389 AD, was a dialogue between Augustine and his son Adeodatus in which they spoke about learning and language. This work mainly was written as a way to explain the structure of dialogue and the language used in said dialogue. The heavy emphasis on signs and signifying reflect the tendency for miscommunication during these types of exchanges. When one engaged in a philosophical debate disagrees on what a sign means, the debate will move in circles without a definition of terms. Therefore, Augustine was emphasizing the importance of definitions before a debate took place and the importance of language in the transfer of knowledge from one person to another. 

On the Teacher builds on the ideas in Against the Academicians in that it was an explanation of how knowledge and truth can be acquired. Augustine proved the existence of knowledge and truth, but without language it was impossible to convey these ideas. Knowledge is, therefore, acquired through language or the exchange of ideas between people engaged in what can be called a conversation. Without the use of language, knowledge cannot existence, at least according to Augustine’s view on learning. Augustine took a more Platonic view on learning: believing that since the soul was immortal, it had knowledge but when it dwelled in the body, this knowledge was lost. The act of learning, therefore, is merely the soul remembering the information that was lost. 

Truth, on the other hand, is a harder concept to grasp, as people seek truth all their lives and sometimes never find it. Augustine, after spending the entirety of his young adult life seeking truth, concludes that the knowledge of truth can only be found through illumination. This theory of illumination is based on the idea that we turn inward when seeking truth, specifically by using reason: “When we deal with things that we perceive by the mind, … we’re speaking of things that we look upon immediately in the inner light of Truth” (On the Teacher, 140). In addition, although we might speak truths, the people who hear the words do not learn from us or the words themselves but, “manifest within when God discloses them” (On the Teacher, 141). Therefore, Augustine believed that God was a necessary part in obtaining the truth because only He discloses truths to us rather than us discovering them on our own. 

According to the Academicians, there was no such thing as knowledge and truth did not exist, which allowed the Academicians to claim that they could get away with remaining in plausibilities rather than in assenting to positions. When these skeptics spoke, they regarded things as ‘truth-like’, meaning that they held an appearance of truth but they refused to assent to it on the basis that there was a probability that it could be wrong. The result of such beliefs led to relativism, the belief that everything could be right and nothing is absolute. However, the idea of ‘truth-like’ contradicts itself in that for something to appear truthful, one would have to have a concept of truth, which would contradict the basis of the Academician’s stance. Augustine took the opinion that knowledge and truth existed, proving that one can, in fact, know truths, even if they are seemingly insignificant. Phrases such as “I am either dead or alive” proved that they held true, as there is no other option between life and death. Without the existence of truth or the accessibility of knowledge, philosophy is completely pointless. If there is no truth, what is the point in searching for it? 

In addition to truth and knowledge, Augustine also emphasized the importance of definitions in philosophical debate. As mentioned previously, it is impossible to have a philosophical discussion when neither party can agree on the definition on what they are arguing on. In both works, Augustine made it a point to start off with the definitions of the very concepts or words that he was using so that the center of debate would not be about definitions, but about more complex ideas. Although debates can arise over definitions, the first step in philosophical debate must always be a definition of terms. Without proper definitions, knowledge and truth cannot be shared between two parties, which is the main purpose of a philosophical dialogue in the first place. 

Both Against the Academicians and On the Teacher were written in the classical dialogue format, meaning that rather than being written in prose, the work takes on the form of a conversation in which people concede or argue opposing points. In terms of education, this structure displays how the ancients believed that knowledge was shared between people, namely in the form of conversations. Students and teacher gathered around, asked questions, elaborate on points, and in the end, they would reach a greater understanding of the topic as a whole. Students were not afraid of being wrong, as, in the end, they would either solidify their point or concede to another, more logical solution. This format of learning relied heavily on the use of logic and reason, each side defending their point until one side conceded to the other’s point. In these conversations, emotions were typically set aside in favor of reason and logic, which in this modern age is almost unheard of as people form their arguments simply based on emotions and tearing the other side down. 

In contrast to the academic skeptics, modern education espouses ‘truth’ but many times fails to explain why these ideas are considered true. Many times, there is a tendency to forget the means because of this heavy focus on the ends. Because of this, it is difficult to debate what we believe is a truth when we do not know why it is a truth, hence the heavy reliance on emotions in modern-day arguments. In a sense, our facilities of reason and logic have become unpracticed and so we accept truths at face value rather than attempt to find why a truth is actually true. Because of this, the study of philosophy became the search for one's own personal truth rather than that of a universal, human truth.

In essence, the modern period has borrowed much from the Academicians in terms of knowledge, morals, and truths. We believe that everyone is right, that everyone will be saved. We claim truths that we cannot even explain and when asked to defend them, we become defensive and emotional. Both Against the Academicians and On the Teacher, though written over six hundred years ago, are still trying to convert us from skepticism to philosophic truth. The lessons Augustine taught - that truth exists and can be found, that knowledge can be attained, the importance of language - are still issues that we struggle to understand.