If one takes a look at the literature on introspection, one can find many metaphors that are derived from visual perception, i.e. that describe the phenomenon as a sort of peering into one’s own consciousness,[3] as well as direct comparisons with visual perception, i.e., stating that the evidential status of introspection is or should be on a par with seeing the outside world. For example, in his depiction of the central idea behind optimism towards introspection, Bayne says that:
Roughly speaking, to regard introspection as able to reveal the phenomenal character of one’s conscious states is to have an optimistic attitude towards it. (Bayne this collection, my italics)
Or take Schwitzgebel, who, in his arguments against the accuracy of introspection, assesses the phenomenon by the standards of visual perception:
Does introspection reveal it to you as clearly as visual observation reveals the presence of the text before your eyes? Can you discern its gross and fine features through introspection as easily and confidently as you can, through vision, discern the gross and fine features of nearby external objects? (2008, my italics)
If one compares this to intuitions, one can see that they are treated in almost the same way. Here, the most prominent historical root of this equal treatment of not only intuitions and perception, but also intuitions and introspection, might be the work of John Locke, who at the beginning of the fourth book of his Essay Concerning Human Understanding states that all knowledge is at its core introspective and intuitive and can thus be regarded as the perception of agreement or disagreement between two ideas:
Knowledge then seems to me to be nothing but the perception of connexion and agreement, or disagreement and repugnancy of any of our Ideas. In this alone it consists. Where this Perception is, there is Knowledge, and where it is not, there, though we may fancy, guess, or believe, yet we always come short of Knowledge. (1975, p. 525, italics in the original)
But contemporary discussions concerning intuitions also suggest a similarity to perception. Take for example this short description by Ernest Sosa:
Intuition gives us direct insight into the general and abstract. (1998; my italics)[4]
For George Bealer, who is maybe the most radical proponent of an intuition-based philosophical methodology, the two phenomena are so closely related that he mentions them both as equal sources of evidence in philosophical theorizing:
So in this terminology, the standard justificatory procedure counts as evidence, not only experiences, observations, and testimony, but also intuitions. […] When one has an intuition, however, often one is introspectively aware that one is having that intuition. On such an occasion, one would then have a bit of introspective evidence as well, namely, that one is having that intuition. (1997, my italics)
This similarity in the way of speaking about the two phenomena and their obvious entanglement in the debate about what counts as evidence[5] gives us information about the explananda themselves. Both intuition and introspection can be consciously experienced by the subject that uses them to make a judgement.[6] Furthermore, they are judged to be epistemically unproblematic, because the subject has direct access to them.
A good example is a classical Gettier-style intuition, such as “It simply seems to me that the person in that scenario does know that she is getting the job” (Gettier 1963). Not only the immediate reaction to Gettier cases, but also the way in which Gettier’s conclusion (i.e. that his thought experiments show that justified true belief does not sufficiently describe knowledge) were widely accepted among philosophers indicates that intuitive judgements are treated as unproblematic and reliable. The same holds for introspective judgements that do not only occur in philosophical debates but also in everyday-life belief formation. An example of such a belief could be expressed by a sentence like: “I surely can’t be mistaken in believing that I am consciously experiencing a red object in front of me at this very moment.” In the same way as in the case of intuitions, the results of introspection do not seem to require further questioning. In short, the act of introspecting something and the act of intuiting something both have a phenomenal aspect that makes them appear epistemically secure. In the course of this commentary this aspect will be referred to as a phenomenology of certainty.[7] In fact, I would say that this phenomenal aspect is the reason why the introspection as well as the intuition debate are as controversial as they are. Both phenomena come at first glance with a seeming of epistemic security (or even infallibility), and only after close examination are some insecurities revealed. This phenomenology of certainty, however, does not immediately show that intuitions and introspection inform a subject securely about the truth of a matter. My introspective judgment about the what-it-is-likeness of understanding a sentence in a foreign language or my intuitive judgment about whether a person has knowledge or not are always in need of further justification. It would be a very hasty step to go from the phenomenology of certainty to full-fledged certainty (Metzinger & Windt 2014).
So then what can the two phenomena inform a subject about? The least controversial description of what introspective states are would be along the lines of (Schwitzgebel’s description:
A word about ‘introspection’. I happen to regard it as a species of attention to currently ongoing conscious experience, but I won’t defend that view here. The project at hand stands or falls quite independently. Think of introspection as you will—as long as it is the primary method by which we normally reach judgments about our experience in cases of the sort I’ll describe.[8] (2008)
Thus construed, introspection mainly informs a subject about the qualitative aspects of her experience. Simply put, what we do when we introspect is to pay attention to the what-it-is-likeness of our experience.[9] This aspect of experience, however, is extremely subjective and private. It is (if even possible) not easy to arrive at scientifically informative generalizations[10] from such subjective data.[11] What is needed to secure information of that kind is the right kind of embeddedness in other, more secure ways of gaining knowledge about a subject matter. Such judgments about a subject’s experience are what Bayne and Spener, at least by the way I understand them, refer to as scaffolded judgments (2010; Bayne this collection). For example, my introspective judgment about my red experience is not exhaustively justified by itself, but by the close match of the content of my introspective state and the non-phenomenal aspects of my visual observation. Only then can introspection play an evidential role,[12] and thus contribute to knowledge about one’s own conscious states. But what if there is no such match? If introspection is concerned with more abstract contents, like, for example, the basic structures of intentionality or thought in general, the lack of embeddedness at least increases the insecurity of the judgment and thus makes it an unreliable source of knowledge. Judgments of that kind, again following Bayne and Spencer, are called freestanding judgments.
Let us now turn to intuitions. What are intuitions about? First of all, it is important to say that not all kinds of intuitions are relevant to philosophical debates. Cases of intuitive controls on a smartphone, for example, are not at the core of the debate. What is meant by philosophically interesting intuitions can be most appropriately expressed by the term conceptual intuition. In short, intuitions in a philosophically relevant sense are judgments that are shaped by the concepts a person has of some subject matter or phenomenon. Usually those intuitions are tested by conducting thought experiments in which a case is described that should (or should not) fulfil all necessary and sufficient conditions of a concept. Then one is supposed to take that very concept and check if it applies to the case (or not). This is why Alvin Goldman also refers to philosophical intuitions as “application intuitions” (2007). Probably the most prominent examples of such intuition-testing thought experiments are Gettier cases. Going back to Edmund Gettier’s famous paper, Gettier cases describe scenarios in which a person appears to lack knowledge, despite the fact that the classical conditions for having knowledge, namely, having a justified true belief, are met (1963). But can these conceptual intuitions in fact inform us about what knowledge is in general, or do those cases simply inform us about our personal concepts? Findings from the fairly new field of experimental philosophy, though highly controversial (Cullen 2010), indicate that conceptual intuitions that have been treated as general intuitions, like those in Gettier cases, are in fact highly idiosyncratic, and thus it is still an open question whether they can lead to generalizations about the concept at hand (Alexander 2012).[13] In other words, one could argue that conceptual intuitions are the reflections of a subject’s idiosyncratic history of concept acquisition (Bieri 2007).
So intuitions—or more precisely their contents—reflect upon a person’s individual, highly subjective concepts. Just like in the case of introspection (which has been shown to be very subjective as well), we need to investigate whether it is possible to move from those personal concepts to general claims about their contents in a reliable way.
I take all of the above-mentioned similarities between introspection and intuition to be sufficient for investigating the reliability of intuitions with conceptual tools and insights that have already been introduced and established to the introspection debate. Thus, I will in the next section try to clarify what counts as an epistemically reliable intuition by applying the distinction between scaffolded and freestanding judgments from the introspection debate to intuitions. In other words, I will investigate intuitions as scaffolded vs. freestanding intuitions (SFIT).
SFIT =Df Due to the similarities between introspection and intuition, one can also distinguish between scaffolded and freestanding intuitions.