> Attributing consciousness to animals based on their responses was seen as a cardinal sin. The argument went that projecting human traits, feelings, and behaviours onto animals had no scientific basis and there was no way of testing what goes on in animals’ minds. What's always been funny to me about the scientific approach to animal consciousness/emotions/empathy is that in a perfectly rational world the default as…
The challenge is that part of an advanced human society is creating black-and-white lines in structures to promote peace and prosperity. For example, everything we associate with the magical age of 18 years old. "Adulthood", sexual consent, voting, drinking, smoking, conscription all begin on an arbitrary day and we take no consideration of the reality of the maturity of the person. (Not to mention that "maturity" is…
That's what cognitive dissonance is. Giving one's senses (in this case the taste buds or the ego 'I' or the mind) more importance than something factual or apparent.
> I am not convinced about the rest of the animal kingdom.
If you take consciousness to mean intelligence, then sure. If you take consciousness to be separate from intelligence and senses, being the energy or force that brings forth the signs of what we call 'life', then I see no reason to believe that every single living entity has consciousness.
The only difference is in the type of body provided to that conscious living entity. Just like how some humans are born without sight, some without hearing, some without the ability to speak. It doesn't mean they're less conscious, they still are an observer observing things through their senses.
Unless and until one can come up with a clear definition of consciousness (you don't need to, just read nyāya philosophy and you'll save thousands of years of efforts), they will not be able to get over their biases based on unintelligent thoughts and cognitive dissonance.