An Alternate Nervous System

The human nervous system consists in part of a brain, with its various lobes, the spinal cord protruding downward, which together form the central nervous system.  The peripheral nervous system encompasses all the nerves that branch away from the spinal cord into other parts of the body.  An average of 86 billion neurons are supposedly found spanning the overall network, relaying electrical and chemical signals for the sake of functions like muscle movement.  Correlations between events in the physical nervous system such as the brain and mental events like the phenomenological experience of sensory perceptions suggest some sort of causal relationship.

It does not follow that one can know which is responsible for the other.  This would be an assumption, not a proven or provable thing, and the mind and nervous system are intertwined but distinct things either way.  It is not even knowable whether the body creates/sustains the mind during biological life (as would appear to be the case) or consciousness actually holds matter in existence.  Few will recognize what does and does not follow, with many assuming that the immaterial nature of consciousness means it must live on after bodily death or that how physical injuries can impair mental capacity means that consciousness is itself physical.  The former is possible but unknown and the latter is outright false.

As humans, people might hear more about human nervous system and its correlative connections to consciousness, but other creatures that outwardly seem to have consciousness lack human neurological structures.  Oceanic animals are quite different from us in this regard.  A sea sponge is living but has no neurons whatsoever, while a sea star, or starfish, has neurons but no brain (like a jellyfish).  Humans have around 86 billion neurons, octopi have approximately 500 million, and sea stars have closer to only 10,000.  Starfishes can still regenerate neurons, regrow lost limbs, or grow severed limbs into separate organisms.

Whereas the octopus has no single centralized brain but still has clusters of neurons for each if its arms, the starfish has a simple nerve ring encircling the mouth that feeds into a radial nerve for each arm.  It does not lack just an endoskeleton, but a brain of any sort.  Despite this, its tube feet still walk or pull apart shelled creatures and its arms can still curl.  It is an animal; it reacts to its environment and to other animals (to feed, for instance).  Though sensory observations of such things do not prove an interior consciousness of any other being, starfishes among them, it would appear that a starfish indeed possesses consciousness.  Even, should this be the case, a lack of elaborate introspective depth or the passion to discover necessary truths would not mean a starfish is not conscious.

Starfishes stand alongside jellyfish, sea cucumbers, and sea sponges as creatures that have no brain yet still have either neurons or no nervous system, not even a "primitive" one.  Scientific laws, correlations, and paradigms cannot be proven beyond the level of potentially illusory perceptions, and one can know from logic alone that consciousness is not the same as the nervous system.  Nevertheless, if an elaborate nervous system or any system is not necessary for conscious life in certain other creatures, then even the contemporary scientific premise of mind-on-neurological dependence is false within its own ideological framework.