Journal Entry of Brentel’s Intuition Pumps and the Proper Use of Thought Experiments

Journal Entry of Brentel's Intuition Pumps and the Proper Use of Thought Experiments

Summary:
Thought experiments are an important method of argumentation for philosophical and scientific theories. However, we should realise that thought experiments is also a way which easily causes fallacies when we praise its merits. "So we have to employ thought experiments carefully." According to Brendel, to use thought experiment, we need to avoid "intuition pumps". How to tread the role of intuition in thought experiments is crucially important.

First of all, let's cketch the outline of Brendel's article. At the beginning, he introduces three kinds of perspectives about the role of intuition in thoght experiments. The first kind of view is given by James Robert Brown who asserts that we gain new information through the help of intuitions. Intuitions in his mind is a priori access to a metaphysical realm. The second kind of view offered by Norton is sharply contrary to Brown's view. He thinks that thought experiments are indeed just arguments without any business with intuition. The last one is Danial Dennett's notion of intuition pumps which mean that thought experiments can lead us to a quick and uncritical jump to a conclusion by appealing to our intuition. Finally, Brendel claims he stands the side of Norton.

Before exposing his thorough critiques, Brendel provides an explication of "thought experiment". Firstly, he points out the similarity between thought experiments and real experiments, that they share the same kinds of certain theoretical requirements, ie., the plandned and controlled change of data, artificial situations on which variables depend, and their dependency on some background assumptions. Secondly, he clarifies their differences, the most obvious one of which is that "the aims of the thought experiment can be achieved without needing to perform a real experiment." Actually, I think all problems of thought experiments listed by Brendel onwards arise from the gap between thought experiment and real experiments, which give intuitions chance to mislead our judgements, because real experiments would pick out any obscure premise in the process of execution and modify them to promote the experiment in a right direction.

In this part, Brentel also lists thought experiments functions and purposes as followings: a) to prove the certain theories or concepts involve contradictions, b) to give supportinng evidence for a theory or a concept, c) to illustrate a complex or abstract position, and/or d) to detect vagueness or the borderline cases of a concept. Maybe because of these merits, we are able to accept thought experiment as a kind of method in theory. Therefore, it becomes more crucial for us to be aware their negative aspect and try to avoid them as Brendel did in the article.

In the third part, Brendel keenly critised Brown's mysterious account of thought experiments which mainly concerns the problem of the informativeness of thught experiments. Brown believes that Platonic thought experiments provides us a distinctive method, a priori access to knowledge, which is different from the empirical or inferential methods of scientific enterprises. Although Brown also admits the fallibility of a priori knowledge, Brendel, like Norton, thinks this kind of account of thought experiments is highly plausible. Firstly, he correctly points out in the example of Galileo's thought experiment that "the intuition that leads us to the conclusion that all bodies fall at the same speed is dependent on and controlled by our ecpirical and scientific knowledge", therefore, "there is no immediate grasp of the relevant laws of nature in the realm of universals". Secondly, he points out another defect of Brown's Platonic account that "it remains entirely unclear when and why an intuitive grasp of the abstract realm can go wrong". In contrast, he argues that "the justification of a thought experiment depends on this account on the justification of the premises involved and the conclusiveness of the inferential steps". Then Brendel offers a new account of thought experiments through reconstucting the same thought experiment. First, by uncovering its hidden premises we can avoid no argumative gap then we do not need Brown's "immediate jump". Second, instead of the intuitive capacity of perceiving the laws of nature, Brendel asserts that "in thought experiment we gain new information by rearranging or reorganizing already known empirical data in a new way and drawing new inferences fro them or by looking at these data from a different and unusual perspective".

Although Bendel shares many points with Norton, he did not go as far as him to claim that all thought experiments really are explicit arguments. He emphasizes the argument but meanwhile admits the role of intution in thought experiments, that is, fuctioning as background in many cases. This is concerned with his naturalistic account of intution. In his mind, "Intutions are best regarded as mental propositional attitudes which are accompanied by a strong feeling of certainty". So, he thinks we need not fly to the opposite extreme denying the value of intuition in thought experiment. To avoid the negative effect of obscure intuition, "we can always make these premises explicit by reconstucting the thought experiment as an argument".

In the fourth part, Brendel focuses one the problem of the legitimacy of the method of thought experiments. He thoroughly committed Dennett's notion of "inntuition pumps" in his argument. To articulate his opinions, he employed many famous examples of thought experiment to strengthen his arguments. But here we would slightly sketch the outline of his scheme.

What is so called "intution pumps"? According to Dennett's interpretation, it a certain sort of thought experiment, which often imploy highly suggestive imaginary scenarios that appeal to intuitions and give rise to particular intuitive conclusions where no rational and critical examination seems to be necessary. However, Brendel is very suspecious upon such sort of experiment and even thinks they are actually dangerous. So, in the following paragraphs, he explicates the reason why a intuition pump is implausible and the way how we could use thought experiments properly.

First of all, "the imaginary scenario should not be under-determined in relevant aspect". Or else it does not fufill the necessary requirement of a controlled change of data and the side-effects of this change. Secondly, the imaginary scenario employed in thought experiments may be specifically described and emblished. We should realise that the general conclusions are not justified by a single and specific example, or else, we may fail into intuition pumps. Thirdly, "counterfactual, fictional or idealized assumptions made in a thought experiment should always be irrelvant." In order to be able avoid the illegitimate employment of relevant counterfactual assumptions, we should try to make all the relevant background assumptions explicit as we can. Finally, thought experiment employed to apply a concept analysis in an unfamiliar situation can also be problematic, because our intuitions are not absolutely stable since they are products of our experence. But Brendel suggests that we should not reject such kind of thought experiments because they will be very helpful to clarify our intuition and analyse concepts as long as we could use them properly.

At the part of conclusion, Brendel summarized his opinions in a short paragraph, emphasizing that intuitions play an important role in the execution and interpretation of thought experiments and that we should employ thought experments carefully since it is easy to be misdirected into a intuition pump by illegitimate imaginary scenarios.

Comments:
I think there is an issue that Brendel ignored or did not clarify clearly, that is, intuitions involved in thought experiments are the parts that need to be uncovered merely for a clear premise for the argument or need also to be justified to be a legitimate premise? In another ward, when we try try to reflect the role of intuition in thought experiment we should not only focus on its cohenrance with the whole argument, but also should pay attention to the legitimacy of the intuition since they are originated from our experience and adaptation to the environment. These intuitions constitute a part of our considered judgments which are competetive with our rational pinciples in some cases. The main work Brendel did in the article seems like to answer the following question: are you sure about premises of your thought experiment? Brendel told us we need to uncover the hidden premises behind our intutions involved in the thought experiment and check it with other parts of the argument. But my further question is that: are you sure the premises you uncovered is legitimate itself? If the premise itself is wrong, the conclusion will be wrong even if the argument starting from the premise is consistent.To respond, you need to provide a justification to ensure me that it is a reasonable premise.

Zhang Ming
August, 2010