Niccolo Negro

What is it that makes a life valuable? A popular view is that life’s moral worth depends in some way on its relationship to consciousness or subjective experience. But a practical application of this view requires the ability to test for consciousness, which is currently lacking. Here, we examine how theories of consciousness (ToCs) can help do so, focusing especially on difficult cases where the answer is not clear (e.g. fetuses, nonhuman animals, unresponsive brain-injured patients, and advanced artificial systems). We consider five major ToCs and what predictions they offer: Integrated information theory, Higher-Order Thought Theory, Recurrent Processing Theory, Global Neuronal Workspace Theory, and Attention Schema Theory. We highlight the important distinction between the capacity and potential for consciousness and use it to explore the limitations in our ability to draw firm conclusions regarding an entity’s consciousness on the basis of each theory.

Advances in animal sentience research, neural organoids, and artificial intelligence reinforce the relevance of justifying attributions of consciousness to nonstandard systems. Clarifying the argumentative structure behind these attributions is important for evaluating their validity. This article addresses this issue, concluding that analogical abduction—a form of reasoning combining analogical and abductive elements—is the strongest method for extrapolating consciousness from humans to nonstandard systems. We argue that the argument from analogy and inference to the best explanation, individually taken, do not meet the criteria for successful extrapolations, whereas analogical abduction offers a promising approach despite limitations in current consciousness science.

Modern science was born when physicists started studying phenomena by recruiting mathematical explanatory frameworks. Since this appears to be the direction followed in recent studies on consciousness, philosophers have to analyze the justification of this third-person methods of explaining a phenomenon that is supposed to be entirely subjective. In this paper I argue that this kind of justification could be found in a certain interpretation of the second-person perspective and I briefly sketch how one of the most promising contemporary theory of consciousness (IIT) could fit with such an interpretation.

In this paper, we revisit the debate surrounding the Unfolding Argument (UA) against causal structure theories of consciousness (as well as the hard-criteria research program it prescribes), using it as a platform for discussing theoretical and methodological issues in consciousness research. Causal structure theories assert that consciousness depends on a particular causal structure of the brain. Our claim is that some of the assumptions fueling the UA are not warranted, and therefore we should reject the methodology for consciousness science that the UA prescribes. First, we briefly survey the most popular philosophical positions in consciousness science, namely physicalism and functionalism. We discuss the relations between these positions and the behaviorist methodology that the UA assumptions express, despite the contrary claim of its proponents. Second, we argue that the same reasoning that the UA applies against causal structure theories can be applied to functionalist approaches, thus proving too much and deeming as unscientific a whole range of (non-causal structure) theories. Since this is overly restrictive and fits poorly with common practice in cognitive neuroscience, we suggest that the reasoning of the UA must be flawed. Third, we assess its philosophical assumptions, which express a restrictive methodology, and conclude that there are reasons to reject them. Finally, we propose a more inclusive methodology for consciousness science, that includes neural, behavioral, and phenomenological evidence (provided by the first-person perspective) without which consciousness science could not even start. Then, we extend this discussion to the scope of consciousness science, and conclude that theories of consciousness should be tested and evaluated on humans, and not on systems considerably different from us. Rather than restricting the methodology of consciousness science, we should, at this point, restrict the range of systems upon which it is supposed to be built.

Phenomenal structuralism is the view that understanding consciousness requires describing its relational and structural properties, a perspective that can have implications for both explaining why experiences feel the way they do and identifying the neural correlates of consciousness. Phenomenal structuralism has gained considerable traction in recent years, with proponents advocating for its adoption as a new paradigm for consciousness science. This paper distinguishes three types of structuralism in consciousness studies: methodological, epistemological, and metaphysical. I critically evaluate metaphysical structuralism, which asserts that the phenomenal character of an experience is fully determined by its relational properties. I present three arguments challenging this metaphysical claim, demonstrating its inadequacy. I also claim, however, that this critique does not affect the fruitfulness of methodological and epistemological structuralism. This analysis clarifies the limits and prospects of the structuralist approach, emphasizing that methodological and epistemological structuralism can contribute to consciousness science without heavy and counterintuitive metaphysical commitments.

In this paper, we revisit the debate surrounding the Unfolding Argument (UA) against causal structure theories of consciousness (as well as the hard-criteria research program it prescribes), using it as a platform for discussing theoretical and methodological issues in consciousness research. Causal structure theories assert that consciousness depends on a particular causal structure of the brain. Our claim is that some of the assumptions fueling the UA are not warranted, and therefore we should reject the methodology for consciousness science that the UA prescribes. First, we briefly survey the most popular philosophical positions in consciousness science, namely physicalism and functionalism. We discuss the relations between these positions and the behaviorist methodology that the UA assumptions express, despite the contrary claim of its proponents. Second, we argue that the same reasoning that the UA applies against causal structure theories can be applied to functionalist approaches, thus proving too much and deeming as unscientific a whole range of (non-causal structure) theories. Since this is overly restrictive and fits poorly with common practice in cognitive neuroscience, we suggest that the reasoning of the UA must be flawed. Third, we assess its philosophical assumptions, which express a restrictive methodology, and conclude that there are reasons to reject them. Finally, we propose a more inclusive methodology for consciousness science, that includes neural, behavioral, and phenomenological evidence (provided by the first-person perspective) without which consciousness science could not even start. Then, we extend this discussion to the scope of consciousness science, and conclude that theories of consciousness should be tested and evaluated on humans, and not on systems considerably different from us. Rather than restricting the methodology of consciousness science, we should, at this point, restrict the range of systems upon which it is supposed to be built.

Assessing the scientific status of theories of consciousness is often a difficult task. In this paper, I explore the dialectic between the Integrated Information Theory, e1003588, 2014; Tononi et al. Nat Rev Neurosci, 17, 450-61, 2016) and a recently proposed criticism of that theory: the ‘unfolding argument’. I show that the phenomenology-first approach in consciousness research can lead to valid scientific theories of consciousness. I do this by highlighting the two reasons why the unfolding argument fails: first, phenomenology-first theories are grounded, not circular. Second, falsificationism does not provide an adequate demarcation criterion in philosophy of science. I conclude that this specific debate has significance for how, in general, consciousness researchers test and criticize theories of consciousness, and how dismissing the phenomenology-first methodology in favour of a third person-based methodology means endorsing a position in philosophy of mind that has already been challenged.

The integrated information theory (IIT) is an ambitious theory of consciousness that aims to provide both a neuroscientific and a metaphysical account of consciousness by identifying consciousness with integrated information. In the philosophical literature, IIT is often associated with a panpsychist worldview. In this paper, I show that IIT can be considered, instead, as a form of emergentism that is incompatible with panpsychism. First, I show that the panpsychist interpretation of IIT is based on two properties of integrated information: intrinsicality and fundamentality. I show that the way IIT deals with these two properties, however, aligns better with emergentism than panpsychism. Then, after plugging some anti-panpsychist assumptions into IIT’s structure, I analyse different philosophical options for interpreting the formal result of causal emergence of integrated information in terms of dependence on and autonomy from its physical substrate. The upshot is that integrated information can be seen as dependent upon the fusion of the cause-effect powers of a physical substrate, and as autonomous in virtue of global-to-local determination. According to this interpretation, consciousness is the constraining power of the system as a whole upon itself, when this power emerges from the fusion on the cause-effect powers of the system’s components.

In consciousness science, theories often differ not only in the account of consciousness they arrive at, but also with respect to how they understand their starting point. Some approaches begin with experimentally gathered data, whereas others begin with phenomenologically gathered data. In this paper, I analyse how the most influential phenomenology-first approach, namely the Integrated Information Theory (IIT) of consciousness, fits its phenomenologically gathered data with explanatory hypotheses. First, I show that experimentally driven approaches hit an explanatory roadblock, since we cannot tell, at the present stage, which model of consciousness is best. Then, I show that IIT’s phenomenology-first approach implies a self-evidencing explanation according to which consciousness can be explained by starting from consciousness itself. I claim that IIT can take advantage of the virtuous circularity of this reasoning, but it also faces a data-fitting issue that is somehow similar to that faced by experiment-driven approaches: we are not given enough information to decide whether the explanatory hypotheses IIT employs to explain its phenomenological data are in fact best. I call this problem “the self-evidencing problem” for IIT, and after introducing it, I propose a possible way for IIT to solve it.

Recently, Kirchhoff and Kiverstein have argued that the extended consciousness thesis, namely the claim that the material vehicles of consciousness extend beyond our heads, is entirely compatible with, and actually mandated by, a correct interpretation of the predictive processing framework. To do so, they rely on a potent argument in favor of the extended consciousness thesis, namely the Dynamical Entanglement and Unique Temporal Signature (DEUTS) argument. Here, we will critically examine Kirchhoff and Kiverstein’s endeavor, arguing for the following three claims. First, we will claim that Kirchhoff and Kiverstein’s emphasis on culture and cultural practices does not help them substantiate the extended consciousness thesis. Secondly, we will argue that the way in which Kirchhoff and Kiverstein formalize the boundaries of a subject’s conscious mind is inadequate, as it yields conclusions running counter some of their assumptions. Lastly, we will argue that the DEUTS argument does not establish the extended consciousness thesis, as it licenses a phenomenal bloat objection which is exactly analogous to the “cognitive bloat” objection to the extended mind thesis. We will thus conclude that Kirchhoff and Kiverstein’s proposed marriage between the extended consciousness thesis and predictive processing fails, and that, contrary to a popular opinion, DEUTS is not a strong argument in favor of the extended consciousness thesis.