forms of life by virtue of a sense of self. Therefore, a sense of self is not discriminative of Consciousness.
2. Consciousness exhibits processing levels more complex than instinct.
3. The presence of memory (short, medium or long term) is not discriminative of Consciousness.
4. Consciousness-qua-Consciousness receives no direct, unmediated sensory input.
Surely it bears asking: What then are the actual positive traits of the Consciousness?
The transition between reptiles and mammals is represented, in the brain, by the development of the cerebrum and the neo-cortex. The neo-cortex is an evolutionarily new layer of grey matter which begins to appear at about the same time as the advent of mammals. As the term “cortex” would imply, the neo-cortex is a new “covering” — a new external layer — of the brain. The old covering, as it were, was grey matter largely associated with the limbic system the descendant of which can still be found in that area in the modern human brain.
In less evolved mammals, by all available evidence, advances are represented by expansion of the white matter of the cerebrum while the neo-cortex remains minimal, incomplete and relatively poorly organized. This expansion of white matter is especially notable in the area called the frontal lobe, an area dedicated to problem solving. With the advent of primates, the neo-cortex thickens and expands to cover the entire brain.
It is not difficult to determine what was the evolutionary advantage of the neo-cortex. The cerebrum being white matter is made up of much longer, heavier nerve processes generally covered in bulky myelin sheaths. It needs considerable space in order process at optimum. It could be compared to an old mainframe computer occupying an entire building with tubes and wires. It can do complex processing but the complexity is limited by the space it requires. In order for the human brain to match its present computing power with only white matter, a fetus’s head would have to be far too large to fit through the birth canal.
The neo-cortex being grey matter, on the other hand, is made up of much shorter, lighter nerve processes protected by a packing of glial cells. The grey matter in the primate neo-cortex is highly organized and closely interconnected. Processing of enormous complexity is possible within a head that, during the fetal stage, will fit through the birth canal.
So then, by virtue of the neo-cortex, vastly more complex processing is possible. It is specialized processing throughout, however. The fact is all to the point.
If we were to imagine the neo-cortex at t=0 (if we may invoke this abstract state to clarify some points), the cerebrum processes precisely as it did before the advent of the neo-cortex. Previously complex processing remains and is un-enhanced. The full set of emotions is installed, as it were. The traditional five senses are functional. The brain can distinguish qualia. The frontal lobe is capable of (to that point) evolutionarily high levels of problem solving. All of this exists and remains in the cerebrum prior to the first neuronal discharge of the neo-cortex. Yet, for all of these capabilities, the brain at t=0 can only be a not-conscious paleo-mammalian brain.
