Boghossian-Style Incompatibilism (Part 1)

Arguments against the compatibility of a priori self-knowledge and content externalism (henceforth, C-externalism) typically fall under one of two headings. First, there is the achievement problem, according to which C-externalism entails that a subject can only come to know the content of her thoughts by examining her environment, and the consequence problem, the charge that C-externalism (when combined with privileged self-knowledge) implies that a subject may have a priori knowledge of empirical facts about her environment.

I will begin with an examination of the achievement problem. Roughly, the achievement problem may be put as follows: C-externalist thought experiments seem to demonstrate that given an appropriate difference in the external world, there will be a difference in thought content, without this difference being reflected in any inner detectable manner. This seems to imply that one cannot tell, without consulting the external world, which of two thoughts one is entertaining, and hence one cannot be said to know what it is one believes or thinks. The intuition underlying a priori incompatibilism is typically illustrated via an appeal to Boghossian-style slow-switch scenarios.

Slow-switch Sue :
Imagine a subject, Sue, who was born and spent most of her life on Earth, where the word ‘tiger’ refers to the creature of the family and genus felidae panthera. However, at some point in the past Sue was secretly transported to Twin-Earth where there are no felidae panthera but only pligers, animals which are visually indistinguishable from felidae panthera but are of a different evolutionary heritage, family and genus. Moreover, Sue is ignorant of the relevant biological facts that distinguish tigers from pligers. Sue is at the zoo, looking at a familiar large striped mammal, and thinks a thought which she expresses with the utterance, ‘that tiger has stripes’. According to the C-externalist, whereas Sue formerly entertained tiger-thoughts, she is currently entertaining a pliger-thought. However, according to the incompatiblist, Sue would fail to notice the change in her environment or her thought contents. If we were to ask Sue whether her thoughts have changed in content after they have in fact done so, she would most likely say they have not. Sue could only know that her thought contents have changed by learning additional empirical facts about her environment. Thus, the incompatibilist concludes that Sue cannot distinguish a priori between the actual situation in which she thinks ‘that tiger has stripes’ and the alternative situation in which she lacks this thought. Thus, Sue’s actual belief that she thinks ‘that tiger has stripes’ fails to constitute an instance of a priori knowledge.

We may unpack the intuition illicited by the Slow-switch Sue example via the following reductio:

(S1) Sue knows, without consulting her environment, that she is entertaining the thought that tiger has stripes.
(S2) Sue knows, without consulting her environment, that C-externalism is true.
(S3) Given (S2), the thought Sue is now entertaining—the tiger-thought—is a different thought than the thought ‘that pliger has stripes’ (the thought she would have in a pliger-world).
(S4) Given (S1), Sue is in a position to know, without consulting her environment, that she is not thinking the thought ‘that pliger has stripes’.
(S5) Given (S1)-(S4), Sue is in a position to know, without consulting her environment, that she is not in a pliger world.
(S6) Intuitively, neither Sue nor anyone else can know that she is in a pliger world without consulting her environment.
(S7) Therefore, if C-externalism is true, Sue does not know, without consulting her environment, that she is entertaining the thought, ‘that tiger has stripes’.

The central intuition on which the above reductio hangs is (S6). I see no reason to question this intuition. To wit, it may be agreed on all sides that a subject can only ascertain that she is in a pliger world by consulting her environment. In my next post, I will limn a compatibilist reply that involves the rejection of (S4).

The 46th International Philosopher's Carnival

A NARROW CROSS-SECTION OF PHILOSOPHY
FROM ACROSS THE WEB

A Philosophy (Pseudo) Conference
Hosted by the Space of Reasons
Monday, April 23rd, 2007

Welcome to the 46^th instalment of the Philosopher's Carnival, which takes the form or a philosophy pseudo-conference, showcasing a narrow cross-section of philosophy on the web. A special thank you goes out to Professor Daniel Dennett for his submission, which raises important questions with regards to what constitutes a worthwhile philosophical research program. In the three "presentations" immediately following the "keynote address" (under the heading of METAPHILOSOPHY), two philosophy students and one non-philosopher share their views on the status and role of philosophical theories. We then turn to the heart and soul of the Carnival which features a number of “presentations” that fall under the heading of Language, Epistemology, Metaphysics and Mind (or LEMMINGS). Finally, we top it all off with a sprinkling of ETHICS and a brief IN DISCUSSION section. Enjoy!

KEYNOTE ADDRESS

Topic: Higher Order Truths about Chmess
Presenter: Daniel C. Dennett


METAPHILOSOPHY

Topic: Theory and Philosophy
Presenter: Peter Schombe

Topic: Thoughts on Theories
Presenter: Adrian Tan

Topic: The Role of Philosophy
Presenter: Quincy Faircloth


LEMMINGS

Topic: Evidence and Armchair Access.
Presenter:Clayton Littlejohn

Topic: A Problem for Externalist?
Presenter: Michael Horton

Topic: Jackson's Mary and Complete Physical Knowledge
Presenter: Ignacio Prado

Topic: Luminosity, Coziness and Borderline Cases
Presenter: Aidan McGlynn

Topic: The Modified Turing Test
Presenter: Christopher Anderson

Topic: Are Causal Facts Observable?
Presenter: Gualtiero Piccinini

Topic: Lewis on Non-Trivial Counterpossibles
Presenter: Joe Salerno

Topic: Infinite Regress and Geisler on Infinite Regress
Presenter: Bryan Norwood

Topic: Libertarian Compatibilism
Presenter: Kenny Pearce

Topic: Arguments for Compatibilism
Presenter: Jeremy Pierce


ETHICS

Topic: Second-Person Reasons and Causally Amorphous Aid.
Presenter: Brian Berkey

Topic: The necessary-condition interpretation of the subjectivity of welfare
Presenter: Michele Loi

Topic: Thom Brooks on “Is Bradley a Retributivist”
Presenter: Thom Brooks


IN DISCUSSION

Our Carnival's discussion section features a brief exchange between Jeremy Stangroom and Richard Chappell on what constitutes "brainwashing"?

Causal vs. Rational Explanations (Part 3)

In my post Causal vs Rational Explanations (Part1) I suggest that the 'Fanatical Tom' objection seems to pose a problem of causal theorists regarding justification. There are two strategies, available to the causal theorist, for responding to this objection :

STRATEGY1: Accept that the Tom has a justified belief, and tweak the causal requirement to reflect this fact.

STRATEGY2: Reject the assumption that Tom has a justified belief.

I believe the considerations presented in my previous post on this topic, Causal vs. Rational Explanations (Part 2), represent a genuine difficulty for attempts to defend causal theories along the lines of strategy1. More specifically, I regard all attempts to argue that the spyware causally sustains Alvin’s believe via an appeal to the notion of a counterfactual cause are moribund.

I now wish to propose an alternative reply, along the lines of STRATEGY2, for arguing that Tom’s belief is not justified. We begin with a few distinctions. First, we must differentiate between the justification of a proposition in the abstract, whether or not anyone holds it, and the justification of a particular subject’s, S’s, belief of a specific proposition p. The first refers to justification of a certain type, what we may call impersonal justification, and the second is justification of a token belief, or personal justification. Impersonal justification does not require any particular believer of p, nor does it presuppose that anyone holds the belief or has expressed it. Thus, what impersonally justifies a belief need not itself be believed by a certain subject. The distinction between impersonal and personal justification is that between general justifiability of the belief that p and S’s being justified in believing that p on some given occasion.
Second, there are several kinds of reasons one may have for holding a proposition as true. Here are four:

(R1) Objective reason is a reason there is for holding a proposition as true. This is a reason whose status as a reason is independent of any subject being aware of it or of its epistemic status. For example, the fact that the thermometer says that temperature of Bob’s son is above normal’ is a reason (in this sense) to believe that ‘Bob’s son has a fever’, whether or not anyone has bothered to consult the thermometer.

(R2) Person-relative objective reason is a reason there is for S, the subject in question, to believe that p. For example, the fact that the thermometer reads 200 is a reason for Bob, but not for Bob’s two year old son who is too young to understand thermometers—to believe that he has a fever. Again, Bob need not actually be aware of this reason.

(R3) Subjective reason is a reason the subject actually possesses for believing that p. Bob possesses a reason to believe his son has a fever when he takes in the fact that the thermometer says his son’s temperature is above normal.

(R4) Operative reason is the reason on the basis of which S believes that p. For example, if Bob came to believe his son had a fever because of his burning forehead, and only then bothered to consult the thermometer, then it would be his son’s burning forehead rather than his thermometer that constitutes his grounding reason.

The first two kinds of reasons provide a subject with propositional justification, or makes some proposition p justifiable. Some proposition or piece of evidence need not be known by anyone in particular in order to constitute a reason in the sense of (R1) and (R2). Although (R1) and (R2) fall short of having a reason, they are both prerequisites for having a reason. (R3) introduces the requirement that the reason be subjectively available and represent the minimal sense in which one may have a reason. (R4) takes this idea one step further by stipulating that the subject base his belief on the reason in question. Signficantly, (R4) captures what is known as doxastic justification, and I believe it is Tom’s failure to fulfil (R4) that accounts for his belief being unjustified.

As the thermometer example illustrates, one and the same reason can instantiate all of (R1)-(R4). Moreover, (R1)-(R4) seems to represent a plausible requirement for a reason to constitute a justifying reason for believing that p. Tom clearly has a reason for believing SPY in the sense of (R1)-(R3). Given the existence of the spyware, there is a normative reason for Tom to believe SPY. The spyware is also a reason for Tom, since he recognises that the spyware constitutes conclusive evidence for the proposition, ‘the NSA is spying on US citizens’. Third, Tom possesses the spyware evidence in the sense that he has it at his disposal.

However, Tom does not have a reason in the sense of (R4). Tom’s belief is not based on the spyware evidence. In short, Tom’s belief is not doxastically justified. This point can also be put in terms of the distinction between impersonal and personal justification described earlier. Tom’s belief that SPY is impersonally justified or justifiable. However, at present we are not merely concerned with whether his belief is justifiable. Rather, we want to ascertain if Tom’s belief is actually justified—to wit, whether Tom is justified in holding his belief. In short, we want to know if Tom is personally justified. Given the doxastically inappropriate basing of his belief, the answer seems to be no.

Philosopher's Carnival: Call For Submissions

The next edition of the Philosopher's Carnival (April 23rd), which will be hosted here at the Space of Reasons, will focus on epistemology (broadly understood), philosophy of mind, and the intersections between the two (e.g., philosophy of perception). However, blog posts in other areas of analytic philosophy are also welcome. Submissions should be roughly equivalent to one or two single spaced pages in length. Ideally, a post should engage a single issue or question and may be argumentative or descriptive. For an example of the overall tone we will be aiming for in the upcoming Carnival, click here. Submissions may be made here.