Introduction: striving for objectivity in space

In this special issue, we put together papers that explore the theme “objectivity, space, and mind” from various angles. In the introduction we minimally discuss what are involved in this theme.

Another important notion of objectivity, though perhaps less common in daily discourses, can be found in P. F. Strawson's writings. For example, in Individuals (1959): I earlier introduced the word "objective" by giving it…a sense in terms of the distinction between oneself and one's states on the one hand, and anything on the other hand which is not either oneself or a state of oneself, but of which one has, or might have, experience…I shall mean by a non-solipsistic consciousness, the consciousness of a being who has a use for the distinction between himself and his states on the one hand, and something not himself or a state of himself, of which he has experience, on the other (1959, p. 69). Evans (1985) is an important follow-up of this, and as Cassam (2005) puts it, here "the idea of an objective world is the idea of a world that can be perceived and exist unperceived" (p. 258; our emphasis). 1 Strawson later comes back to this discussion in the context of Kant's Critique of Pure Reason: As the investigation proceeds, however, we become aware that the word "object" is to be taken more weightily than we might at first have thought. It means something more than merely a particular instance of a general concept. It carries connotations of "objectivity." To know something about an object, e.g., that it falls under suchand-such a general concept, is to know something that holds irrespective of the occurrence of any particular state of consciousness, irrespective of the occurrence of any particular experience of awareness of the object as falling under the general concept in question. Judgements about objects, if valid, are objectively valid, valid independently of the occurrence of the particular state of awareness, of the particular experience, which issues in the judgement. (1966, p. 73).
This Strawsonian notion of "mind-independence," though has less bearings in daily life, is perhaps even more important for our purposes, since the current theme is "objectivity, space, and mind," and one way (though not the only way) for an item to be mind-independent is to be located in physical space.
There is a historical reason why space plays a crucial role here. Philosophy has a long tradition of worrying about the existence and our knowledge of the external world; philosophers have been concerned with the question whether there is anything existing outside the mind, and if so, how we can know about them. Given these spatial metaphors, no wonder space and objectivity are very often considered together. 2 For Thomas Hobbes, the very idea of mind-independence just is the notion of things existing in space (1656/2011). This might be more plausible if we restrict attention to perceptual objectivity, though the exact relations between perception and objectivity remain to be seen. A similar view is due to Descartes with his dualism, according to which whatever is objective is also physical, i.e., has spatial magnitude (1641/1996; second meditation). Kant further develops the connection between the spatial and the objective in intricate ways; here is just one relevant passage: [I]n order that certain sensations be referred to something outside me (that is, to something in another region of space from that in which I find myself)…the representation of space must be presupposed. The representation of space cannot, therefore, be empirically obtained from the relations of outer appearance. On the contrary, this outer experience is itself possible at all only through that representation (Kant 1787(Kant /2007: A23/B38; emphasis added).
One key thing here, amongst others, is to understand exactly what Kant means, and what we should mean, by "outside me." Without qualification, this modern strand of thinking might have trouble accommodating abstract objects or systems such as mathematics. This continues to influence more contemporary thinkers in the twentieth century; specifically, they worry about explaining objectivity of abstract entity with non-physical objects (e.g., Benacerraf 1965, Dummett 1975, Quine 1980, Field 1989. This is less important for us, since the current theme is "objectivity, space, and mind," and within this territory, what concern us are concrete things that are located in space. The Strawsonian notion is not limited to Strawson's own writings. For example, although the Strawsonian objectivity is probably never W. V. O. Quine's topic in any explicit way, his writings have deep implications in this regard: his notion of "stimulus meaning" (1960) makes it difficult to understand how intentionality can have objective import, according to some critics. His rather sceptical views about reference and ontology (1953,1969) might also generate difficulties in reconstructing a sensible view of objectivity from his outlook. Donald Davidson (1984Davidson ( , 2001 follows Quine in many regards, but he offers a less sceptical and more systematic framework that does include resources to account for objectivity. One distinctive point of his view is that objectivity comes in only with robust linguistic capacities, especially in his discussions of triangulation and the second person. 3 More recently, John McDowell (1996) has been recommending a comprehensive picture of the relations between kinds of minds and the objective world. His worldview might strike some as threatening objectivity, especially due to his "unboundedness of the conceptual" doctrine, since according to one reading (the idealist reading) it eliminates mind-independence all together. Kantian themes in this regard never really fade away. Christopher Peacocke (1994) introduces his edited volume Objectivity, Simulation, and the Unity of Consciousness like this: Though Kant no doubt read rather more into this presupposition than we would today, there would still be general agreement that all thought about the objective world, from advanced scientific theory to everyday reasoning, directly or indirectly, requires the thinker to grasp spatial notions (1994, p. xi; our emphasis).
Here again, the importance of space is brought up. This abstract description leaves open exactly how we are going to cash out the relations between objectivity and space. For example, how should we understand "grasp spatial notions"? Which spatial notions are involved, and in what ways? Do human infants and other animals fulfill this requirement?
Later in his paper "Objectivity" (2009), Peacocke defines his notion of "minimal objectivity" like this: "a thinker's being in the state, or enjoying the event, does not in general make the content of the state or event correct…Having a perceptual experience as of something being the case does not in general make it the case" (p. 739). He emphasises that this minimal notion does not imply mind-independence, for this reason: Some judgements display minimal objectivity and have contents whose truth is mind-independent; but other minimally objective judgements have contents whose truth is mind-dependent. On some classical views of secondary qualities, the truth of a judgement "That apple is red" consists in facts about certain possible perceptual experiences of the apple as red. Provided the experiences are distinct from a thinker's making a particular judgement "That apple is red"as they arethe condition for minimal objectivity of the judgement is met. (Peacocke 2009, p. 740).
If Peacocke is right about this case, then indeed his notion of minimal objectivity is weaker than our notion of mind-independence, though they are not entirely unrelated.
The most comprehensive treatment of objectivity in the perceptual domain in recent years is probably Tyler Burge's tour de force, Origins of Objectivity (2010). He distinguishes several notions of objectivity, including the two introduced above. He emphasises the metaphysical nature of the Strawsonian notion by using another difficult notion, "constitutively" (p. 46). Here is not the place to detail what it means; suffice to say that something is constitutively mind-independent if and only if its existence (constitution) does not depend on any mental act. The other one is close to (or perhaps even identical to) Nagel's "point of view" conception. What is crucial is that he seems to make a further point here by connecting this conception of objectivity with veridicality condition and representational content (p. 47). On the face of it, this is a substantive further move since some philosophers accept the perspectival conception of objectivity but reject representational content as applied to perception. We shall not go into this debate here, but just to acknowledge that one reason why certain notions of objectivity are still under heated discussions nowadays is partly because they have convoluted connections to notions of representational content, which is central to contemporary philosophy of mind and philosophy of perception.
With this broadly Strawsonian line of thought, we can understand the current theme with this vivid question: how does the mind strive for objectivity in space? How do experiences and thoughts, as subjective states and episodes, reach out the world and gain objectivity? A framework provided by Quassim Cassam (2005) is helpful. According to Cassam, there are at least three versions of "Spatiality Thesis" to in the literature (2005: 260-1): (ST E ) The existence of space is necessary for objective experience. (ST I ) The idea of space is necessary for objective experience. (ST P ) The perception of space is necessary for objective experience.
Yet another version of the Spatiality Thesis, which is not covered by Cassam, can be this: (ST A ) The action within space is necessary for objective experience.
Cassam argues that while both Strawson (1959) and Evans (1980) primarily concern (ST E ) and (ST I ), Kant (1787Kant ( /2007) focuses more on (ST P ). However he also points out that they are all intertwined in one way or another, so a satisfactory discussion of objectivity and spatiality cannot make clear-cuts between them. (ST A ) is a possible view in light of the recent enactivist movement (e.g., Noë 2004), but how plausible it is with the current formulation and how it interacts with other versions are yet to be explored. In his other works, Cassam have explored different versions of the Spatiality Thesis (1997,2007). In a similar vein but with some empirical twists, John Campbell (2007), John Schwenkler (2012), Craig French (2018, and Cheng (2019) have debated whether the case of Bálint's Syndromewith which patients can see only a visual target at one time but are unable to localise that target's location, and perhaps should be said to have no visual field at allis a real-life counterexample of certain versions of the Spatiality Thesis about vision.
To be sure, there is no need to think of the "striving for objectivity in space" question with Cassam's framework, in which necessary conditions and transcendental connections are central. But it does provide one fruitful way of conceiving of the relevant issues.

Papers and motivations
In the present issue, we have compiled six papers from Rick Grush & Alison Springle, Frank Jackson, Filip Matten, John Schwenkler & Assaf Weksler, Mark Textor, and Charles Travis. Some of the authors are working within the Strawsonian tradition, while others might be less sympathetic. One thing we would like to emphasise is that two papersfrom Filip Matten and from Mark Textorare commissioned specifically with the intention to bring the phenomenological tradition to bear. This is based on the conviction that objectivity, space, and mind should be considered with the insights from continental phenomenology. A good example is Cassam's Self and World (1997), in which he nicely blends in some discussions from the phenomenological point of view, specifically notions of the body. For Husserl, the Body (der Leib) is the "animated flesh of an animal or human being," i.e., a bodily self, while a mere body (der Körper) is simply "inanimate physical matter" (1913/1998, p. xiv). The Body presents itself as "a bearer of sensations" (ibid., p. 168). A similar distinction emerges in Merleau-Ponty's work as between the phenomenal/lived body and the objective body that is made of muscles, bones, and nerves (1945/2013). There is a debate concerning whether it should be interpreted as between different entities or different perspectives of the same entity (Baldwin 1988). 4 Just as the case of Kant's transcendental idealism, the two-world/entity view is in general more difficult to defend, but it does not mean that this interpretation should be rejected out of hand. One Anglo-Saxon twist of the tradition is the "sensorimotor approach" (de Vignemont 2011); the followers include Hurley (1998), O'Regan and Noë (2001), Noë (2004), Siewart (2005, and Thompson (2005). Here in not the place to dive in the relevant details, but the potential relevance of the phenomenological tradition should be fully acknowledged.
This special issue is partially based on the following two events: Objectivity, Space, and Mind (BPPA Masterclass, co-organised by Tony Cheng, Alisa Mandrigin and Vanessa Carr, London 2015) and Spatial Experience (New Directions in the Study of the Mind, co-organised by Tony Cheng and Alex Kerr, U.C. Berkeley 2017). These occasions have provided rich grounds for the present special issue, and for future investigations as well.
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