Here's a paper written which spells out the dilemma taken from Behavior Online:
So, are some animals conscious? We see now that the question itself is irrevocably tied to the human conscious experience, because human consciousness is all we can imagine. Consider a more fruitful enquiry, in my regard: How do animals interact with each other and their environment, and why do they behave in those ways? We can construe answers to these latter questions without the equivocation that discussions of consciousness carry in cross-species analyses. Further, we can build models of animal behaviour from a base of absolutely minimal assumption, exploring their world as one alien to our own rather than searching it for qualities that are familiar to us. It may well be that some animal species outside Homo sapiens share sensory experience akin to ours; to that end we would like to treat consciousness not as an all-or-none quality but something that can exist to many degrees. One may object: How could we study animal cognition this way? It’s impossible to imagine being half-conscious, or a third conscious! Yes, exactly: animal mental states may be so foreign to us that representing them would be akin to conveying eleven dimensions on a flat piece of paper. Rather than leaping into a cursory attempt at knowing exactly how non-human animals think and feel, it may be wiser to study the consequences, which are readily observable, of their mental states. Let us treat animal minds as an unknown landscape that acquires shape by virtue of its shadows, which we see in their behaviour. Dawkins takes steps toward this approach at the end of her book, but her analysis of emotional expression in animals again presupposes in them a degree of human consciousness. After describing an experiment on hen behaviour, the author suggests that, in their effort to reach nest boxes, hens “experience a strong state of frustration at not being able to find one” (Dawkins 1998, 155). This passage may seem relatively innocuous, but in fact it assumes that hens are conscious animals with mental states so similar to our own that they can “experience . . . frustration.” Her description makes no sense unless we take it in stride that hens are conscious like we are, at least in the limited context of emotional response. It is precisely such slips of thought and diction that we must avoid.
Explaining human conscious experience is among the most daunting and exciting projects modern science faces. The progress we’ve made to that end is exhilarating and uplifting, but, tempted as we may be to do so, extending our intuitive inferences about human minds to animal minds is not conducive to understanding cognition outside our species. Why: because those inferences carry tacit assumptions about human mental worlds, which do not apply to non-human mental worlds. We will probably never be able to put ourselves into animals’ shoes, so to speak, but we can certainly build extensive, impartial records of animal minds’ input and output. By exploring the patterns in those input and output records, we can achieve a greater understanding of cognitive architecture outside Homo sapiens.
Boyer, P. Religion Explained. New York, USA: Basic Books: 2001.
Dawkins, M. S. Through our eyes only? The search for animal consciousness.
Oxford, UK: Oxford University Press: 1998.
Dennett, D. C. Consciousness Explained. Boston, USA: Back Bay Books: 1991.