Stuff to think about

The first was delivered to us by Mr. John L. Austin, the second one by Mr. David Hume, the third by Mr. Thomas Hobbes.

You have a donkey and so do I and they graze in the same field. The day comes when I conceive a dislike for mine. I go to shoot it, draw a bead on it, fire: the brute falls in its tracks. I inspect the victim, and find to my horror that it is your donkey. I appear on your doorstep with the remains and say… what? “I say, old sport, I’m awfully sorry, etc. I’ve shot your donkey… by accident? or by mistake?” Then again, I go to shoot my donkey as before, draw a bead on it, fire – but as I do so, the beasts move, and to my horror yours falls. Again the scene on the doorstep – what do I say? “by mistake”? or “by accident”?

***

Suppose therefore a person to have enjoyed his sight for thirty years, and to have become perfectly well acquainted with colours of all kinds, excepting one particular shade of blue, for instance, which it never has been his fortune to meet with. Let all the different shades of that colour, except a single one, be plac’d before him, descending gradually from the deepest to the lightest; ’tis plain, that he will perceive a blank, where the shade is wanting, and will be sensible, that there is a greater distance in that place betwixt the contiguous colours than in any other. Now I ask, whether ’tis possible for him, from his own imagination, to supply this deficiency, and raise up to himself the idea of that particular shade, tho’ it had never been cnoveyed to him by his senses?

***

The Ship of Theseus has its parts gradually replaced and the old parts are stored and eventually made into another ship. Which is the original ship?

TE's + modal logic = LOVE (?)

Damper, R. (2006). The logic of Searle's Chinese room argument. Mind, 16(1), 163-183

In this article, Robert Damper attempts to bring out the benefits of a quasi-modal formalization of thought-experiments, with a direct application on John Searle’s Chinese Room Argument (CRA, henceforth). Since thought experiments are clearly dealing with what can or could be the case, and reasoning in some manner from these “ifs and cans” – to borrow Strawson’s title – the step seems only fitting.

Here’s a concise restatement of Searle’s CRA:

Searle envisages a situation in which he is hidden in a room and is presented questions in Chinese written on an ‘input’ card, posted in to his room by unseen enquirers. Searle knows no Chinese; indeed, he is quite unaware of the enterprise in which he is engaged and is ignorant of the fact that the strange marks on the cards represent questions framed in Chinese. He consults a manual telling him (in English) precisely what equally strange marks to write on an ‘output’ card, which he posts back to the outside world. By virtue of the ‘machine intelligence’ embodied in the manual (which is actually a formalisation of the steps in an AI program), these marks on the output card constitute an answer to any input question. […] Searle concludes that an AI program could give the impression of intelligence to an external observer, but have no understanding. This is contrary to the tenets of strong AI—essentially that computational states are functionally equivalent to mental states—as exemplified in the (then contemporary) work of Schank and Abelson (1977), McCarthy (1979), Newell (1980) and others. (p. 165)

Amongst many replies to this thought experiment, the one called “systems reply” is the most debated and to which many rejoinders have been given on each side. Damper summarizes the discussion as follows:

• Systems reply: intelligence resides in the total system not just in Searle himself, who is merely a component. Because a part of the system (i.e. Searle) does not understand Chinese, this does not mean that the complete system does not understand Chinese. 166
• Searle claims to have the decisive rebuttal which he calls the ‘outdoor’ CRA. He argues that he simply (!) ‘internalizes’ everything, committing the entire manual to memory, and then proceeds as before. There is then, he argues, nothing but the human in the system who still does not understand Chinese 166
• The popular rejoinder by proponents of AI to this manoeuvre is to point out that it begs the question by assuming the truth of the CRA

Damper borrows from Sorensen’s Thought experiments (1992) a classification as well as a quasi-formalization of thought experiments. (I say “quasi-” because what the “form” indeed shows is a reduced version of the thought experiment. Not the story itself, but a line-up of the proposition that might constitute it, should it be re-stated in the form of an argument)

In these terms, we replace the general model with the particularities of CRA:
1. The modal source statement is the ‘theory’ of strong AI, namely that executing an AI program is necessarily constitutive of understanding.
2. The modal source statement S implies the logical necessity that any implementation of the Chinese-understanding program understands Chinese, in accordance with the tenets of strong AI.
3. If Searle were to hand-implement any such program then he would understand Chinese—a ‘weird’ consequence, W.
4. Searle does not understand Chinese (this is an ‘absurdity’).
5. It is possible that Searle can hand-implement the Chinese understanding program.

From the fact that 1-5 are inconsistent (in some way, usually logical), the thought experimenter draws the conclusion that S must be wrong.

The advantage of doing this – and continuing to work with this framework in dealing with the replies, too – is that we can see, in a more transparent way, the manner in which the thought experiment is being put forward. For instance, we can clearly delineate, in the case of a “refuter” (or “destructive TE”), what is the theory against which the experiment functions. Also, we can separate the replies more clearly into no more than five types, according to the step they do not allow. Thirdly, we can identify fallacies and antifallacies (seemingly good steps that are bad, and seemingly bad steps that are good, respectively).

Little is said about these fallacies. Damper borrows from Sorensen the idea that a common fallacy (common to thought experiments only?) is missuposition, which “comes in two flavours”: oversupposing and undersupposing. The first case is that of admitting to much, creating flamboyant worlds and scenarios the possibility of which becomes suspect. The second – a fault which Damper finds in Searle’s CRA – is that of keeping the background assumptions to an ambiguous minimum. “Searle occasionally remarks on the simplicity and ‘conciseness’ of the CRA.13 Yet this very conciseness is in my view no more than a symptom of undersupposing.” (p. 177)

Although it might be true that Searle leaves out parts which might turn out to be important – in some respects – I think this is a very very weak refutation of Searle’s endeavour. It is hard to see what, of the relevant parts, is left out, and it is hard to believe so many people debated to and fro about this thought experiment without requiring an answer to what is in fact an essential question. Damper exemplifies, but unconvincingly: “how it is able to answer context-dependent questions (like ‘what was the question that I asked just before the last one?’)”. Plus, the fact that some important part is missing – and the recognition of any of the fallacies mentioned above, actually – is in no need of the formalization. The link between the (quasi-formal) translation and the replies is clear, but the link between the formal translation and the fallacies is practically absent. One could have accused Searle of not being specific enough, or being too exotic in his assumptions without having formalized his thought experiment beforehand.

PS: It is my impression that Damper assumes – without necessarily making it explicit – two strong propositions as being true: (1) that Searle’s thought experiment is an argument. One argument, that is. (2) that modal logic would tell us anything (new) about the TE. After all, how do we know that this or that formalization is a good one, unless we already have, and use, some criteria that are already there.

Slowly, about thought experiments

Cooper, R. (2005). Thought experiments. Metaphilosophy, 36(3), 328-347

Thought experiments were broadly defined by Gendler (1998) as reasoning as to what would be the case if some state of affairs described in an imaginary scenario were actual. Indeed, thought experiments are, first and foremost, epistemologically fascinating: “In a thought experiment, it seems we can start from a position of ignorance, sit and think, and gain new knowledge, despite the input of no new empirical data” (Cooper, 2005, p. 328). Thought experiments are “merely” mental because their application in practice would be impossible or unethical or extremely expensive.

Cooper argues, first, for the benefits of a unitary view of thought experiments. Both the science/philosophy distinction, and the distinction between different types of thought experiments, he argues, are thus not very useful. The first because of the ambiguous border between science (e.g. linguistics) and philosophy (e.g. of language). The second, because of the common reasoning going on in all thought experimentation. Cooper then goes on to examine different “accounts” on thought experiments.

Thomas Kuhn, for instance, in his paper “A function for thought experiments” (1964) contends that thought experiments as some sort of (Platonic?) remembering of previous knowledge. In periods of “normal science”, the scientist usually sees anomalies – unless he explained absolutely everything – but moves on, for his endeavour is usually focused, and cannot tackle everything. Thought experiments, or at least some of them, have the function of building up this knowledge into a scenario, so that the anomaly itself is not “lost” or “forgotten”.

John Norton is of the rather different opinion that thought experiments are the enjoyable attire of what are really just arguments. More often than not, reductio ad absurdum arguments. In several papers (Norton, 1991; 1996), he set to show that many of Einstein’s thought experiments can be reproduced in the more familiar structure of argumentation – that is, of premises leading to a certain conclusion.

James Brown (not the singer!) offers another Platonic account: thought experiments help us perceive some sort of Platonic realm of things and discuss them in their generality. Thus, in physics, when we use a concept “thought experimentally”, we do it with capitals: we use Mass, Strings, Choice etc. Cooper notes: “In addition, even if it were possible to perceive universals, Brown’s Platonic heaven would need to be repulsively overpopulated. For these reasons his account should be countenanced only as a very last resort.” (Cooper, 2005, p. 334)

Experimentalist accounts consider that thought experiments are just experiments. These accounts accept the obvious differences but hold that the similarities are greater and more important. As an objection to this, Cooper notes: “I’m not sure what to make of claims that thought experiments are literally experiments. It’s not as if experiments form a natural kind, such that it might be discovered that thought experiments are a species of the genus. Rather than being a claim like ‘Whales are mammals,’ the claim that thought experiments are experiments seems more like ‘Beanbags are chairs.’” Some authors such as Sorensen (1992) go in a slightly different direction by saying that thought experiments are in fact paradoxes since they correspond to a set of intuitively plausible yet inconsistent propositions.

The next step in Cooper’s paper is to spell out his “better account” of thought experiments as “attempts to construct models of possible worlds” (p. 336). He stresses the centrality of intuitions and even points out that the reasoning going on in a thought experiment is of a very common nature. The only difference is that the philosopher/scientist tries to follow these intuitions rigorously, consistently, justifiably etc. That is, she “follows through all the relevant implications of altering one part of her worldview and attempts to construct a coherent model of the situation she is imagining”.
It is not so very straightforward, however, what makes an implication relevant, and whether there is such a performance as considering all the relevant implications.

Consider, for example, the thought experiment in which Einstein considered what he would see if he ran along a light beam at the speed of light. Now, of course, anyone running at such speeds would be in no position to make observations: long before reaching light speeds they would be too tired to notice anything, and their running shoes would burn up. Such points, however, are irrelevant to the issues at hand and so can be ignored.

To Cooper, then, constructing and using thought experiments is something like making a model. So long as the commitment to consistency and rigour is held up, whether this model is mental or visual is not really material to the point of the experiment. For instance, if the thought experimenter constructs a model – actually a set of possible worlds, where the relevant propositions are true regardless of the status of the irrelevant ones – and concludes to the possibility of that scenario, she has thereby arrived at the knowledge that “X” is possible. (Is this new knowledge? Yes, according to Cooper, they “teach us” (p. 339) whether this or that is possible in our actual world)

The background assumptions – or “relevant descriptions” of the possible world – are very important because it is these that the experimenter works with. It is in connection to these that Cooper discusses the ways in which a thought experiment may fail. First, the assumptions might be such that clear implcations would not be possibly drawn.

I suggest that Bernard Williams’ thought experiment concerning people that split like amoebas is an example of a thought experiment that fails, because we are unable to answer the necessary ‘‘what if’’ questions (Williams 1973, 23). We can ask, ‘‘What if people split like amoebas?’’ But we are unable to answer. How exactly could people split like amoebas? Would they split down the middle and have one leg and one hand each? In that case they would fall over, and unless skin suddenly grew to cover their wounds, their organs would fall out. Or are they supposed to split into two mini but complete people? Then, presumably, prior to splitting, a person would have to sprout an extra head and extra legs and arms. Either way, the biological logistics required to get the scenario off the ground are too complex and gruesome to work out.

A second way in which experiments may fail, a more obvious one, is if the experimenter claims consistency where that is none, or vice versa. Cooper concludes by re-stating the advantages of seeing thought experiments as intuition-based "models".

PS: At this stage, it is unclear to me what these people are "explaining". Sometimes, two "accounts" compete in being a better description, sometimes in being a better answer to a problematic question. Neither Cooper's "account" nor the previous one she outlined were decided as to what it is they are answering or resolving.