1. Consciousness can exist as pure awareness state (without thought, emotions, forms, etc.) which is a state I reach during meditation. You can have one without the other!
2. Simple forms of life (no complex brain needed), e.g. plants and fish, possess consciousness.
3. Experience. This goes back to point 1 and how I perceived reality while in a pure conscious state. All matter is simply a manifestation of an indivisible field of Consciousness. Read more: Using field research (Meditation) to discover Consciousness.
When Danmark asks how a rock is conscious I think that he's supposing that it could only be conscious if it has feelings, processes information from sensory receptors, etc. But again, consciousness does not have to exist with all of these things. It comes in degrees; its most basic form is pure awareness. Consciousness exists and is expressed differently between awake humans and those in vegetative state or between fish and plants or computers and rocks. It seems scientists do not know where to draw the line when it comes to where consciousness exists.
One label for my view is "panpsychism". Here's a good article explains it:
Quartz article.Consciousness permeates reality. Rather than being just a unique feature of human subjective experience, it’s the foundation of the universe, present in every particle and all physical matter.
This sounds like easily-dismissible bunkum, but as traditional attempts to explain consciousness continue to fail, the “panpsychist� view is increasingly being taken seriously by credible philosophers, neuroscientists, and physicists, including figures such as neuroscientist Christof Koch and physicist Roger Penrose.
The materialist viewpoint states that consciousness is derived entirely from physical matter. It’s unclear, though, exactly how this could work.
Dualism holds that consciousness is separate and distinct from physical matter
Panpsychism offers an attractive alternative solution: Consciousness is a fundamental feature of physical matter; every single particle in existence has an “unimaginably simple� form of consciousness, says Goff. These particles then come together to form more complex forms of consciousness, such as humans’ subjective experiences. This isn’t meant to imply that particles have a coherent worldview or actively think, merely that there’s some inherent subjective experience of consciousness in even the tiniest particle.
Given that consciousness can exist or function in a simple form, then what proof is there to show that consciousness is limited to mammals? Why not fish, plants, computers, and other inanimate matter? Perhaps you don't know?