Hellenistic Epistemology

PHI 420. Writing Assignments

Each of the four writing assignments is worth 10 points. Several have multiple parts. Be sure to write your answers in such a way that a reader who does not already know the material can understand what you have written. The best way to do this is to provide detailed answers.

Assignment #1

On the JTB analysis of knowledge, a subject S knows a proposition P just in case (i) S is justified in believing P, (ii) P is true, and (iii) S believes P.

For discussion of the JTB analysis of knowledge and of the analysis of knowledge more generally, see The analysis of Knowledge (Stanford Encyclopedia of Philosophy).
According to the Stoics, is what one knows true? Be sure to explain your answer.

On the Stoic understanding, all knowledge is cognition but not all cognition is knowledge. Why? In your answer, be sure to explain how the Stoics understand "cognition."

Which understanding of knowledge is more plausible, the JTB analysis or the Stoic understanding? Be sure to give reasons for your answer.

Assignment #2

There are different ways to formulate the argument the Academics press against the Stoics. This is especially true for premise (1). Charles Brittain, for example, states the premise in terms of the "phenomenal content" of impressions ("Introduction," On Academic Scepticism, xxii).

Arguments have premises and a conclusion. The function of the premises is to support the truth of the conclusion. To "present, explain, evaluate" an argument is to provide a three-step analysis of the underlying reasoning and over all plausibility of the argument. To "present" an argument is to set out its premises and conclusion. To "explain" an argument is to provide the evidence for the premises and for thinking that the truth of the premises establishes the conclusion. To "evaluate" an argument is to determine whether it is sound. An argument is sound just in case it is valid and its premises are true. An argument is valid just in case its conclusion must be true if its premises are true.

In the "extract, explain, evaluate" model of how to understand arguments in philosophical texts, the explanation of the premises in an argument occurs in the "explain" section of the discussion. For premise (1), the idea is that for every true impression one has, the situation is indistinguishable in a certain way from a situation in which one has a false impression. So, for example, suppose that someone is looking at twin A and has the impression that "This is twin A." The Academics invite the Stoics to think that no matter how good the light is, how wide awake the person is, and so on, for all the person knows the impression he has comes from looking at twin B, not twin A.

The indiscernibility of identicals is the thesis that if x and y are identical, then x and y are indiscernible.

Note that if x and y are identical, then "x" and "y" are two designations for one and the same object.

The identity of indiscernibles is the thesis that if x and y are indiscernible, then x and y are identical.

A version of the indiscernibility of identicals is a traditional part of classical first-order logic. The identity of indiscernibles is not. It is more controversial.
Against the Stoics, the Academics press the following argument:

  1. For every true impression, there is a false impression indistinguishable from it.
  2. If (1) is true, then no impression is cognitive.
  3. If no impression is cognitive, then it is necessary to withhold assent.
  4. It is necessary to withhold assent.

The Stoics reject premise (1). What are their reasons? In your answer, explain how the identity of indiscernibles figures in the reasons the Stoics give for rejecting premise (1).

Assignment #3

The Stoics replied to the Academics with an argument of their own: that life would be impossible to live if no impression were cognitive because impulse, and thus action and life itself, requires assent. In response to this Stoic argument, Carneades put forward the view that even if their are not cognitive impressions, assent is permitted because there are "persuasive impressions."

There are two interpretations of what Carneades had in mind. It might be that he was simply arguing dialectically and thus that he did nothing more than put forward the view about "persuasive impressions" as part of a counter argument to this Stoic argument. Alternatively, it might be that Carneades was arguing dialectically but that he also thought that assenting to impressions in terms of their persuasiveness is the ordinary way to form beliefs which the Stoics wish to replace with their new method in terms of cognitive impressions.

Explain how this second interpretation of what Carneades had in mind would allow the Academics to reject a premise in the argument (in assignment #2) against the Stoics. In your answer, be sure to identify the premise and to explain how this interpretation saves the Academics from the absurdity of assenting to the view that no one should assent to any view.

Assignment #4

In the Academy, there was a dispute between the Clitomachians and the Philonian/Metrodorians about how to understand Carneades and assent to "persuasive impressions." Brittain attributes to Clitomachus and the Clitomachians the view he calls "radical scepticism" (On Academic Skepticism, "Introduction," xxvii). In describing this view, he says the following.

"[W]hen the Academics draw their notorious conclusions about the unattainability of knowledge and the irrationality of forming beliefs, they are maintaining only that these conclusions are currently 'persuasive'; they are not committed to the truth of these views or of the arguments that support them. But in that case, the Clitomachian Academics do not believe, e.g., that nothing can be known, or, at least, they do not believe it in the sense implied by Stoic assent. It is perhaps unclear how we should (or even can) make sense of this position..." (xxvii).

Words can have more than one sense. So, e.g., the word 'cape' can have the meaning "land jutting out to sea" or "article of clothing worn over the shoulders."
Kinds and senses are not the same. A Macintosh Red is a kind of apple, not a sense of the word 'apple.'
What does Brittain mean when he says that "the Clitomachian Academics do not believe, e.g., that nothing can be known, or, at least, they do not believe it in the sense implied by Stoic assent"? In your answer, be sure to explain why he suggests that this "position" may be incoherent.

Bibliography Project

The bibliography project is worth 20 points. It is a summary and assessment of the argument in five journal articles or book chapters from the scholarly literature on issues related to the debate between the Stoics and the Academics. In your summary, you are to outline the argument and make a judgment about its plausibility. In this way, the bibliography project is a set of notes about what you have read and to which you can return in the future. Here is an example.

• "Carneades' Distinction Between Assent and Approval,"
Richard Bett. The Monist, Vol. 73, No. 1, 1990, 3-20.

Bett explicates what he takes to be Carneades' distinction between "assenting" to and "approving" or "following" an impression (4). For Carneades, according to Bett, whereas to assent "is to take a stand on the truth of the impression," to approve an impression "involves no commitment ... as to whether [the content] is really true or false" (10). To illustrate the difference, Bett gives an example. "1) A person takes a left turn, while en route to a certain house. The action is intentional, but is not the result of any conscious deliberation. 2) The person is not familiar with the route. She wonders whether to take a left turn, in light of the evidence afforded by her map, prominent landmarks, etc.; having considered the matter, she takes the left turn. In doing so, she thinks to herself 'it seems to me plausible that this is the route'; she does not think to herself 'Yes; this really is the right way to go.' 3) The same as 2), except that she does think to herself 'Yes; this really is the right way to go' (and not, or not only, 'it seems to me plausible that this is the route')" (10-11). Bett says that for Carneades the first two cases are "approval" and the last is "assent" (11).

I doubt that Bett's interpretation is correct.

Bett seems to think his example shows that someone might act in terms of a belief but not "take a stand on the truth" of the propositional content of this belief, but I doubt the example really shows this. In all three cases, it seems to me that the agent is acting on the belief that "the left is the turn to make to get to the house." Further, by believing this and representing the world in this way, I think that the agent is "tak[ing] a stand on the truth" of the propositional content of this belief. So it seems to me that the distinction Bett attributes to Carneades is a distinction in name only.

Does the textual evidence show that Carneades understood his distinction between "assent" and "approval" in terms of "tak[ing] a stand on truth" in the way Bett claims?


Academica 103-104 does suggest that Clitomachus thought that Carneades distinguished between "assent" and "approval," but it does not show that he understood his distinction in the confused way that Bett's interpretation attributes to him. To attribute this view to Carneades, the textual evidence must be explicit. This is not true of the evidence for Carneades' distinction.

go back go back