The traditional conception of knowledge, originally subscribed to by Plato and forwarded by Descartes, has attempted to define knowledge by separating what constitutes genuine knowledge from what is mere opinion or groundless belief. This definition, which ultimately accepts knowledge to be justified true belief, is presently still being debated and analyzed. Contemporary deliberation on this issue, however, does not center completely upon whether or not one should ascribe to this definition of knowledge, but rather, whether or not one should subscribe to a weak conception of justification or a strong conception of justification, and more importantly, whether or not that justification can be ascertained from a first person perspective. The strong version aims for a guarantee of truth, while the weaker version targets a perhaps more realistic probability of truth. Laurence BonJour in his book, Epistemology, tackles this classical problem head on by clearly articulating the differences between the two conceptions while outlining the problems and solutions inherent in each. He ultimately mounts a defense of the Cartesian project in an attempt to preserve a rigorous, if unattainable, ideal of knowledge. He states, “However problematic the strong conception of justification may be…its intuitive significance and importance is clear.” (Epistemology, Pg. 43) Whether as an ideal to aspire to, or as a normative claim, the strong conception of justification, according to BonJour, remains a bastion of philosophical inquiry.

In order to motivate further the aforementioned distinction between the strong and weak versions of the traditional conception of knowledge, we must first delineate the Cartesian underpinnings of this strong view. As such, we can best understand the Cartesian conception of knowledge as a strong version aimed at achieving certainty or indubitability. This struggle for certainty entails the advancement of an argument based on the following three conditions, which are both necessary and sufficient for Cartesian knowledge to obtain:

For Descartes, a knower S knows a proposition P IFF:

1. S believes/accepts P without any doubt

2. P is true

3. S is justified in believing that P because S has a reason that guarantees that P is true

Thus, we must ask, under these three conditions, what precisely passes for certainty and its inherent strong justification? Or, more importantly, can we obtain Cartesian indubitability? Since Descartes was an internalist, he believed that the content of one’s own experience, or the things that are recognizable to the knower herself constitutes the first piece of knowledge. In other words, first-person epistemic judgments have an undeniable logical priority over third-person epistemic judgments. Secondly, since he is a foundationalist, he posits that there exist a small amount of self-evident facts that can be known a priori. These analytic facts are those that one can conceptualize in one’s own mind. Lastly, Descartes states that we can rely on all of the metaphysical and epistemological principles that can be derived via these a priori beliefs, as long as we utilize our reason correctly.

Subsequently, the Cartesian account can be adequately generalized into three necessary conditions, which then form the basic foundation for all other accounts of the traditional conception of knowledge, both strong and weak. They are:

1. Belief or acceptance condition

2. Truth condition

3. Justification condition

So, now we must examine, what are the core differences in how each version treats these conditions? Fundamentally, the main separation occurs within the context of how strongly a knower must accept and justify what it is that he or she believes. Under the strong version, a knower S knows a proposition P IFF P is guaranteed to be true. Under the weak conception, a knower S knows a proposition P if S has evidence that indicates that P is at least likely to be true. Thus, it is clear that this distinction will yield very different consequences, with very different positive aspects and worries. Yet, how do we decide which is correct? In order to decide, it is necessary to consider the implications and outcomes of each condition individually and mutually.

We’ll begin with a discussion of the first condition, or that of belief and acceptance. Under the strong conception of knowledge, this condition stipulates that a knower cannot pass for knowledge any proposition that he or she has ever doubted as being true. In other words, anything that one is not completely certain of, one cannot know. Under the weak conception, however, this condition becomes a degree of acceptance or a question of how confident one is in a belief. As such, under the weak conception, the worry clearly is, at what point do we actually consider something to be knowledge? Does something need to be 99.9% certain or will a simple majority of 51% suffice? When analyzing this question, it is important to realize that this condition broadly covers both dispositional belief, or a belief that one would assent to if consciously aware of (S would believe that P if S were to consider that P and accept that P), and occurent belief, or a belief that one is consciously aware of and assents to (S believes that P). This broad coverage allows for the entailment of unconscious but clearly acceptable beliefs, as well as the commonsense judgments that are essential to our understanding. For this reason, however, we must also speculate on whether the threshold of Cartesian indubitability is too strong and, more importantly, whether or not it is even possible to obtain. On the other hand, perhaps we may decide that its obtainment is not necessary.

The second condition, or the truth condition, is simply that. Clearly one cannot know what is not true. This is “something that almost no philosopher has seriously disputed.” (Bon Jour, Pg. 32) The question arises, however, how we can recognize whether a proposition is true. Well, according to both versions of the traditional conception of knowledge, an appeal must be made to the reasons or justifications for it. It is for this reason that the truth condition may only be recognized via our justification, and, as such, must be satisfied in conjunction with the other two conditions. As such, the most widely accepted view of what truth is is the correspondence theory of truth. This notion dictates a commonsensical account of truth by simply stating that if something is true, it corresponds to a relevant aspect of something in the world. Or, in other words, this two-part theory bridges the gap between the two entities of your mind and reality.

The third condition, or that of justification, stipulates that one must possess a strong truth conducive reason for believing that the proposition in question is true. The easiest way to achieve this epistemic justification is to have evidence that favors the validity of the proposition in question. Or, in some cases, such as three angles form a triangle; the epistemic justification can be self-evident. Thus, again the discussion centers upon how strong this justification must be in order to qualify as knowledge. Within the confines of both the Cartesian and the strong conception of knowledge the justification must be conclusive. And, again, for the weak conception, the justification must be reasonably strong or at least likely. So, which endeavor should we appeal too? According to BonJour, “It is fairly easy to see the appeal of the strong version of the reason or justification condition and the strong conception of knowledge that results. If…the aim of our cognitive endeavors is truth and our reasons or justifications are our means for achieving this goal, then only a reason or justification that satisfies the strong version of this condition allows us to be sure that the goal has in fact been achieved; with anything less than this, success would be to some extent uncertain.” (Ibid, Pg. 41)

Hence, as an unrivaled model, should we subscribe to a strong Cartesian version of the concept of knowledge? The response, in my opinion, should be a resounding yes. Beyond the worry that we may end up possessing virtually no knowledge whatsoever, the strong conception gives us an ideal to aspire to. Whether or not we can rise to its attainment it is unimportant and negligible. After all, is it not the case that most ideals are rarely achieved? The simplistic fact that ideals might be unattainable does not mean that we should abandon them. As such, if we can view knowledge as an ideal cognitive state that contains both certainty and justification, we can acquire a solid basis for our epistemic inquiry. Consequently, reason, as a reference to the Cartesian viewpoint of clear and distinct, becomes the perception that allows us to determine what knowledge is. And, importantly, this can be, and generally is, underestimated by our common sense beliefs. It may well be the case that our pragmatic conceptions of knowledge allow for an unspecified or unsatisfied level of justification, but this should not force us to lower our standard. As such, we should embrace the Cartesian Project as an ideal, while realizing that we will more often than not, fail in its attainment.