Animal Sentience
October 29, 2026
Oryan Zacks
In The Edge of Sentience, the sentience candidacy of fishes and reptiles is strengthened if one accepts midbrain-centric theories of human consciousness. In this commentary I attempt to untether the two positions. I suggest that we need not look for a one-to-one match between the neocortex and a single pallial structure outside of mammals. Instead, a sufficient similarity might exist between...
Animal Sentience
October 12, 2026
Jon Mallatt, Todd E Feinberg
We discuss some of the many valuable insights into affective sentience from Birch’s The Edge of Sentience, such as its eight criteria for determining which entities have sentience (e.g., emotions) and its insights into the difficulty of testing whether an Artificial Intelligence system has attained sentience. We add our own perspectives on why the eight criteria are valid, on the difficulty of...
Animal Sentience
September 22, 2026
Claudia Passos-Ferreira
Birch proposes that human fetuses be recognized as sentience candidates from 12 weeks, on the grounds that midbrain-centered theories fall within the zone of reasonable disagreement among theories of consciousness. I raise a methodological and a policy problem for his view. Methodologically, whether the midbrain-centered view belongs within the zone is disputed, so there is no consensus about...
Animal Sentience
August 28, 2026
Catherine Macri, Martín Giurfa
What does The Edge of Sentience tell us about insect sentience and consciousness? In this commentary, we reflect on Jonathan Birch’s framework for defining and scientifically investigating sentience in animals. We discuss the methodological challenges of studying subjective experience in evolutionary distant species, and consider trace conditioning, affective states, and neural architectures as...
Animal Sentience
August 3, 2026
Carolyn A. Ristau
Donald Griffin co-discovered bat sonar and founded the field of echolocation. He studied bird migration and founded Cognitive Ethology, the study of animal awareness and mental experiences. In all these endeavors, he faced hostile opposition. The biography (Ristau 2024) examines Griffin's life and the scientific explorations by him and others in these fields. This Précis emphasizes his...
Animal Sentience
August 3, 2026
Luis H. Favela
Woodruff (2017) argues that teleost fishes are capable of phenomenal consciousness. Central to his argument is the assumption that phenomenal consciousness is representational in nature. I think the commitment to a representational theory of consciousness undermines Woodruff’s case for teleost phenomenal consciousness. The reason is that organisms do not need to perceive the world indirectly...
Animal Sentience
August 3, 2026
Jon Mallatt
Mather (2019) presents convincing evidence that octopuses have minds, but in the first 85% of the target article, the evidence does not come through very clearly because it is hidden by other information and by problems with the paper’s organization. I propose ways to build a tighter argument in the author’s Response to the Commentaries.
Animal Sentience
August 3, 2026
Mark Solms
The criteria for determining animal sentience proposed in the target article are sensible but they lack an explicit functional justification for the focus on pain. This commentary provides an abbreviated account of the most basic functional principles that underpin animal sentience and articulates some minimal criteria for determining its presence.
Animal Sentience
August 3, 2026
Riccardo Manzotti
Key (2016) claims that fish do not feel pain because they lack the neural structures that have a contingent causal role in generating and feeling pain in mammals. I counterargue that no conclusive evidence supports the sufficiency of any mammalian neural structure to produce pain. We cannot move from contingent necessity in mammals to necessity in every organism.
Animal Sentience
August 3, 2026
Donald M Broom
Neither sentience nor moral standing is confined to animals with large or human-like brains. Invertebrates deserve moral consideration. Definition of terms clarifies the relationship between sentience and welfare. All animals have welfare but humans give more protection to sentient animals. Humans should be less human-centred.
Animal Sentience
August 3, 2026
Lynne U. Sneddon, Matthew C. Leach
Key (2016) affirms that we do not know how the fish brain processes pain but denies — because fish lack a human-like cortex — that fish can feel pain. He affirms that birds, like fish, have a singly-laminated cortex and that the structure of the bird brain is quite different from that of the human brain, yet he does not deny that birds can feel pain. In this commentary we describe how Key cites...
Animal Sentience
August 3, 2026
Paco Calvo, Miguel Segundo-Ortin
In our target article (Segundo-Ortin & Calvo 2023), we proposed the intriguing possibility of plant sentience, drawing parallels with non-human animal studies. This response aims to sift through the rich thicket of perspectives offered by our commentators. To do so, we assess the risks of employing double standards, as well as the tendencies of anthropomorphizing and zoomorphizing in plant...
Animal Sentience
August 3, 2026
Mark Rowlands
Several types of objection have been raised against the arguments I presented in my target article, “Are animals persons?” Among the objections are the following: (1) the claim that animals are persons is of little significance, (2) my use of the Lockean conception of the person is questionable, (3) whether a creature qualifies as a person is a matter of social construction rather than...
Animal Sentience
August 3, 2026
Bjørn Grinde
Carolyn Ristau has done a fine job summarizing the work and life of the zoologist Donald Griffin. Most scientists now accept the existence of animal sentience, but identifying which species possess consciousness remains controversial. Griffin defined consciousness as "the subjective state of feeling or thinking about objects and events.” Nonconscious processes are faster and more...
Animal Sentience
August 3, 2026
Colin Klein, Andrew B Barron
Our target article, “Insects have the capacity for subjective experience,” has provoked a diverse range of commentaries. In this response we have collated what we see as the major themes of the discussion. It is clear that we differ from some commentators in our commitments to what subjective experience is and what the midbrain is capable of. Here we clarify where we stand on those points and...
Animal Sentience
August 3, 2026
Brian Key
Klein & Barron (2016) propose that subjective experience in humans arises in the midbrain and then argue that insects have the capacity for subjective experience because their nervous system can perform neural processing similar to that of the midbrain. This approach ultimately fails because it is built on the false premise that the midbrain is the source of the awareness of sensory stimuli. I...
Animal Sentience
August 3, 2026
Irina Mikhalevich
Woodruff (2017) claims to have identified the neural correlates of phenomenal consciousness (“p-consciousness”) in fishes, and argues that these neurological data, along with behavioral evidence, suggest that teleost fishes are in all probability sentient organisms. Woodruff’s case may be strengthened by challenging key assumptions behind a common criticism of accounts such as his: that fishes...
Animal Sentience
August 3, 2026
Michael L. Woodruff
In my target article, I argued that the brains of ray-finned fishes of the teleost subclass (Actinopterygii) are sufficiently complex to support sentience — that these fishes have subjective awareness of interoceptive and exteroceptive sense experience. Extending previous theories centered on the tectum, I focused on the organization of the fish pallium. In this Response to the commentaries, I...
Animal Sentience
August 3, 2026
Gwen J. Broude
Reber believes he has simplified Chalmers’s “hard problem” of consciousness by arguing that subjectivity is an inherent feature of biological forms. His argument rests on the related notions of continuity of mind and gradual accretion of capacities across evolutionary time. These notions need to be defended, not just asserted. Because Reber minimizes the differences in mental faculties among...
Animal Sentience
August 3, 2026
Jennifer Mather
Because cephalopods are so different from the vertebrate lineage, their possible consciousness must be assessed on the basis of their heritage and abilities. Cephalopods have evolved in water, a denser medium than air, and their perception is adapted to it. They have inherited the molluscan mantle cavity and hydrostatic muscle type, which has led to a more distributed motor control system...
Animal Sentience
August 3, 2026
Yew-Kwang Ng
Reber’s axiom: “Any organism with flexible cell walls, a sensitivity to its surrounds and the capacity for locomotion will possess the biological foundations of mind and consciousness” does not seem to be supported by things we know and the logic of evolutionary biology. The latter leads to the conclusion that conscious species are flexible in their behavior (rather than in their cell walls),...
Animal Sentience
August 3, 2026
Brian Key, Deborah J Brown
Mikhalevich & Powell argue that the exclusion of the vast majority of arthropods from moral standing is unwarranted, particularly given the purported evidence for cognition and sentience in these organisms. The implied association between consciousness and moral standing is questionable and their assumption that rich forms of cognition and flexible behavior are dependent on phenomenal...
Animal Sentience
August 3, 2026
Andrew Y. Lee
This commentary is about whether sentience, or what philosophers call “phenomenal consciousness,” comes in degrees.
Animal Sentience
August 3, 2026
Gordon Burghardt
Jennifer Mather has provided a comprehensive and fascinating overview of the various cognitive accomplishments of cephalopods and their sensory, behavioral, and neurophysiological attributes. The advances in our understanding of a clade that has been separated from vertebrate evolution by well over half a billion years is a testament to advances in both methodology and the questions we now feel...
Animal Sentience
August 3, 2026
Arthur S. Reber
The commentaries by Calvo (2018) and Mallatt & Feinberg (2017) on my 2016 target branch out from a common conceptual node like forks in a road. Calvo criticizes me for not acknowledging that plants too are likely to be sentient and claims I have fallen into the kind of category error of which I accuse others ─ a zoocentric bias that fails to grant consciousness to flora. Mallatt & Feinberg...