Does Nozick Offer A Satisfying Response To The Sceptic?

This paper elucidates the theory of knowledge by Robert Nozick and illustrates how the approach responds to scepticism. The essay revolves around an argument which suggests that Nozick’s response to a sceptic argument is not satisfying, thus objecting the theory in a general view.

Nozick’s Theory of Knowledge

According to the theory, S knows p if only; (1) p is true (2) S believes p (3) if p is not true, S would not believe p (4) if p is not right, S would believe p.  Whereas the first two conditions; (1) and (2) are forthright, the last two states need an explication (Forbes, 1984). The third condition doesn’t say that not-p involves not-(S believes p). Instead, it means in all possible worlds where not-p is right; they are very close to the reality, not-(S believes p) is similarly true. This condition is meant to a coarse elucidation of the third state. We require a metric on possible worlds’ space to make it definite. Similarly, the fourth condition does not say p involves (S believes p). Instead, it says that in all the possible worlds where p is true, and that is very close to the reality, (S believes p) is also right.

We notice that the third and fourth conditions are very much related to the condition which states that p causes S’s belief of p. There are several cases whereby the fact of p creating S’s belief of p implies that the third and fourth conditions are satisfied. In such cases, the account of Nozick agrees with the cause theory by Goldman regarding the knowledge ascriptions. Nozick does not give us a metric, and it is surprising as it turns out to be a formidable task. It is highly possible that Nozick has a metric in mind, but it’s not formulated. We only get a rough idea of what is going on in his mind by evaluating different examples. Nevertheless, the causal theory is nowhere close to the account of Nozick.  Some cases satisfy the causal condition but never meet conditions (3) and (4). There are also other cases which meet the two conditions but fail to satisfy the causal condition.

Nozick holds that his theory, which is also known as the conditional theory of knowledge, beats the following sceptical arguments. (1) I don’t know that I’m not a brain in a vat. (2) If a person was to know that p involves q and he was supposed to know p, then he would probably know q. (3) I know that by sitting down to write an essay involves the implication that I’m not a brain in a vat. Therefore, I don’t know I’m sitting down writing an article. The conditional theory of knowledge approves the first proposition.  Considering that I am aware that I am not a brain in a vat, the following conditions would hold; (i) It is true I’m not a brain in a vat (ii) I do believe I’m not a brain in a vat (iii) if I were a brain in a vat, I wouldn’t believe I am not a brain in a vat (iv) if I were a brain in a vat I would still believe I’m not a brain in a vat.

Condition (iii) doesn’t hold regardless of whether or I am not a brain in a vat in the real world and in all other possible worlds that considers me a brain in a vat, I still believe I am not. Because condition (iii) is not right, Nozick’s theory insists that I don’t know I am not a brain in a vat. Nozick’s theory agrees with the premise (iii), but on the other hand, it disagrees with the conclusion (Garrett, 1983). The sceptical argument does not only tend to indicate that I don’t know I am sitting down to write an essay. Instead, it purports to suggest that I almost don’t know anything. The sentence, ‘I’m sitting down to write an article’ can be replaced by any other sentence that describes an ordinary state of affair.

Nozick is in agreement with premises (iii) and (iv) of a sceptical argument and its concluding statement. Assuming that the case is authentic, then he has to reject premise (ii), and this is exactly what he does (Greco, Sosa and Zagzebski, 1998).  This second proposition is referred to as the closure principle as it holds that knowledge is closed in a logical implication. The conditional theory of knowledge is in disagreement with the closure principle due to the disclosure of conditions (3) and (4) in a logical implication. It might be true that (3)* if p weren’t true, S wouldn’t believe p and (K) S knows p to entail q. However, these conditions aren’t enough to make sure that (3)* if q weren’t true, S wouldn’t believe q.

As an illustration; suppose p is a statement, “S was made in London, ” and q is another statement “S was made on Earth.” It is likely that (3) and (K) would be true while (3) would not be true. There is no single reason to substantiate the truth of (3) and (K) and adequate to clarify the closest worlds where S was not made on Earth. In this case, S doesn’t believe it was made on earth. Therefore, condition (3) of the truth’s conditional theory isn’t closed in a known logical meaning, and hence knowledge is not at all enclosed in a logical implication.

Objection from DeRose

Keith DeRose argues that it is counter-intuitive to reject the closure principle. He writes that accepting Nozick’s treatment entails embracing a detestable conjunction that although you may not know you are a bodiless and possibly handless, you will still know that you’ve got hands. Lightly, DeRose’s reply to a sceptical argument begins with a rejection of the argument’s first proposition. DeRose can be described as an epistemic contextualist.   Theories of contextualising epistemologies about the value of truth in the inscriptive knowledge are sensitive to particular facts about a speaker as well as hearers of a context. Furthermore, there are certain cases whereby it’s sincere to say S is aware he is isn’t a brain in a vat and he is actually ignoring the possibility of being a brain in a vat. In such contexts, premise (1) of the sceptical argument usually fails, and as a result, the conclusion of the argument doesn’t follow.

The contextualists and Nozick theories have worked pretty well, and they succeed to take out part of the force of a sceptic argument (Landesman, 1999). It is evident why we may argue that the theory by Nozick has a counter-intuitive attribute. It is counter-intuitive to find one speaker honestly saying that S knows p and at the same time another one in a context which is different from that of the first speaker, indeed saying that S does not know p. Such scenarios offer a flat analogy to demonstrate the meanings differently. It seems that one speaker could say “Q is flat” and at the same time another one in a different context say truly that “Q isn’t flat.” For instance, a driver driving on a particular road may find the way to be flat, but at the same time, a road maintenance worker who is looking for bumps would conclude that the road isn’t flat. Contextualists use such analogies to bring forth a persuasion of the way they view knowledge ascriptions without counter-intuition. Lewis (1996) states that ignoring does not mean we aren’t thinking in any way but instead it implies our awareness of the possibilities, but we rather put them aside.

There is another argument that objects Nozick’s theory. Some practices of externalism reject justification as a knowledge condition as claimed by Nozick. Such explanations provide a fascinating interpretation of what it’s for a belief to establish a track of truth or correct information without giving a knowledge account. The reason for this is that no one understands whether what he accepts is the truth when it would be as well reasonable for one take the opposite based on the available information. An indispensable normative condition for a person to know p is more sensible for one to accept p than denying p based on the available information that one can access. Such a case implicates the need for a condition which can justify a case.

The objection is an appeal to intuition. Nozick’s theory doesn’t require a knowledge bearer to discern justification for an actual belief. Kripke (2011) holds that such a case runs a counter-intuitive understanding of what it means to know something. Kripke’s argument has an intuitive appeal. However, there are some legitimate reasons for it to take the form that it has. The argument can apply to a contextualist theory, but it needs further investigation.  The open inadequacy of the theory lies in the Gettier problems it faces.