Traditionally, consciousness has been treated as an exclusive club. Humans are unquestionably members. Most animals are often assumed to be on the outside. Plants, fungi, bacteria, and machines are typically regarded as little more than biological or mechanical systems lacking any real awareness.
However, a recent review published in Frontiers in Psychology argues that science could be asking the wrong questions and making incorrect assumptions about consciousness.
Dr. Jeff Sebo, a philosopher and professor of environmental studies and bioethics at New York University, explores an intriguing issue in modern science and philosophy: what kinds of beings should we assume are conscious before definitive proof exists.
Rather than focusing only on humans or familiar animals, Dr. Sebo’s analysis examines whether plants, fungi, bacteria, AI systems, robots, and perhaps even all matter itself could possess some form of subjective experience.
While it may sound like a mere philosophical debate, perceptions of what qualifies as consciousness influence a wide range of fields, from biomedical research to the ethical principles guiding humanity’s relationship with nature and emerging technologies.
“Questions about the distribution of consciousness in the world arise constantly in both science and ethics,” Dr. Sebo writes. “These assumptions shape everything from research design and laboratory protocols to farming practices and wildlife management policies.”
Historically, science has often assumed that nonhuman beings lack consciousness. Over the past few decades, however, a growing body of research has increasingly challenged that view, with studies suggesting that many animals—including chimpanzees, dolphins, octopuses, and even insects—possess surprisingly sophisticated cognitive abilities and can exhibit signs of self-awareness, emotion, planning, and tool use.
In 2024, forty scientists and philosophers, including Dr. Sebo, signed the New York Declaration on Animal Consciousness. The decree states that, based on the mounting empirical evidence, there is a “realistic possibility of conscious experience” in many animals. Support for the declaration has expanded dramatically, with the number of signatories growing to nearly 600 scientists and philosophers as of May 2026.
In his recent paper, Dr. Sebo takes the consciousness debate further by challenging the long-standing assumption that nonhuman beings lack consciousness unless overwhelming evidence proves otherwise. He argues that this default skepticism may actually be holding science back.
“The traditional skeptical assumption about nonhuman consciousness may be too restrictive given the current state of evidence and theory,” Dr. Sebo writes. “When we search for evidence with an open mind and non-anthropocentric methods, we tend to find at least some indicators of subjective awareness across a wide range of biological and artificial systems.”
Instead of treating consciousness as a simple yes-or-no question, Dr. Sebo analyzes several possibilities for how consciousness may be distributed across the natural and artificial world, and examines the default assumptions scientists use when evidence remains uncertain.
One possibility is that all animals are conscious. Similarly, the concept holds that all living beings are conscious, including plants and fungi. A third prospect is the idea that any organism capable of processing sensory information may possess awareness. Another approach centers on complex cognition, potentially extending consciousness to future AI systems.
The most radical possibility is panpsychism, the philosophical idea that consciousness is a fundamental property of matter itself. However, Dr. Sebo cautions that even if simple forms of consciousness existed at the level of matter, further theory would be needed to explain how, or whether, complex conscious experience emerges in larger systems.
Dr. Sebo does not argue that a single default assumption about consciousness is always best. Instead, he argues that scientists and ethicists may need different assumptions for different purposes, depending on the evidence, the research question, and the ethical risks involved.
“We should select different default assumptions about the distribution of consciousness for different purposes and in different contexts, both within and beyond the animal kingdom,” Dr. Sebo writes. “Overall, the aim is to balance theoretical rigor with practical progress, recognizing that assumptions work differently when taken as truth claims and when taken as mere tools.”
One of the central challenges to understanding consciousness is that it remains notoriously difficult to study.
Scientists can observe behavior, brain activity, and information processing, but subjective experience itself cannot be directly accessed from the outside. In philosophy, this is known as the “problem of other minds.” Humans cannot directly verify another being’s inner experience in the same way they can access their own.
“We can directly observe behaviors and anatomies, but not thoughts and feelings,” Dr. Sebo writes. “These epistemic barriers limit our ability to draw firm conclusions about which beings are conscious.”
The inherent inability to observe subjective awareness has led researchers to develop new approaches, including the search for so-called “markers” of consciousness in animals and even in AI systems. By comparing humans and nonhumans, scientists hope to identify similarities that indicate the presence of subjective experiences in animals and in technology.
However, these techniques may have significant limitations because they rely heavily on identifying markers that resemble human consciousness. If consciousness exists in many forms, some animals and potentially future AI systems could exhibit signs of awareness fundamentally alien to human experience, making them much harder for researchers to recognize.
The paper also revisits the so-called “hard problem of consciousness,” the enduring mystery of how physical systems like brains produce subjective experience at all. Even if neuroscience eventually explains how the brain processes information, researchers will still struggle to explain why those processes feel like something from the inside.
Because of the profound uncertainties surrounding consciousness, Dr. Sebo argues that rigid skepticism toward nonhuman awareness may no longer be scientifically justified. Instead, he suggests researchers may benefit from a more flexible, probabilistic approach. Rather than treating entities as either conscious or mindless, scientists could assign varying probabilities of consciousness based on the available evidence.
Adopting this more holistic approach to consciousness could have profound ethical implications, as it would force people to rethink their attitudes towards animals, plants, and artificial intelligence.
If a creature or machine has even a modest chance of experiencing suffering, Dr. Sebo argues society may need to consider the moral risks of ignoring that possibility. Mistakenly treating a conscious being as a mere object could allow enormous harm.
The analysis compares the dangers of false positives and false negatives. Mistakenly treating a nonconscious object as conscious could waste resources or encourage unnecessary emotional attachment. But mistakenly treating a conscious being as though it lacks feelings or awareness could allow suffering on a massive scale.
“At the theoretical level, our defaults should ideally balance the risk of false positives and the risk of false negatives,” Dr. Sebo writes. “At the practical level, our defaults should also reflect what particular agents are able to achieve and sustain at present and what will build momentum toward a better calibrated moral circle in the future.”
The argument becomes especially complicated in the context of artificial intelligence. As Dr. Sebo notes, advanced AI systems could eventually force society into deeply difficult ethical territory.
On the one hand, if future AI systems become capable of mimicking human behavior convincingly enough to persuade society they are conscious, people may eventually face pressure to grant them rights or legal protections.
On the other hand, the paper argues that granting rights or political standing to machines that are not actually conscious could create serious societal dangers. Beyond deepening humanity’s dependence on advanced technologies, Dr. Sebo notes that some experts warn such decisions could even introduce existential risks if increasingly powerful AI systems were treated as entities with genuine moral or political standing.
“The result could be human disempowerment, perhaps even extinction—all for the sake of entities with no inner mental life,” Dr. Sebo writes.
At the same time, Dr. Sebo cautions against dismissing AI consciousness outright under a default stance of skepticism. He notes science’s long history of underestimating animal consciousness serves as a warning about the risks of assuming unfamiliar minds are impossible.
Rather than arguing for a single universal standard, Dr. Sebo emphasizes that different situations may require different assumptions about consciousness. Scientific theory, practical research, ethical theory, and real-world policymaking all involve different risks and goals, meaning each may require its own approach.
For example, scientists trying to open new lines of research may benefit from broader assumptions about consciousness, while policymakers designing regulations may need more cautious, incremental standards.
One of the paper’s most striking themes is that consciousness may not be a rare phenomenon restricted to humans and a handful of advanced animals. Instead, the universe may contain a far wider spectrum of minds than humanity can currently imagine.
That possibility carries profound implications for fields ranging from neuroscience and philosophy to agriculture, environmental policy, robotics, AI development, and even the search for extraterrestrial life.
Ultimately, the idea also raises deeply unsettling questions about humanity’s relationship with the rest of existence—and whether people may have vastly underestimated the presence of conscious experience in the world around them.
“The stakes of our default assumptions about the distribution of consciousness are high,” Dr. Sebo concludes. “As progress continues, our default assumptions about the distribution of consciousness could shape our decisions in a range of contexts, determining the trajectory of consciousness science and the fates of countless entities.”
Tim McMillan is a retired law enforcement executive, investigative reporter and co-founder of The Debrief. His writing typically focuses on defense, national security, the Intelligence Community and topics related to psychology. You can follow Tim on Twitter: @LtTimMcMillan. Tim can be reached by email: tim@thedebrief.org or through encrypted email: LtTimMcMillan@protonmail.com