The psychule is a proposed model for a fundamental type of event related to mind/sentience/consciousness. The term "psychule" is meant to be analogous to the term "molecule" as the fundamental unit of a substance, except that a psychule is not a substance but an event.  I would like to say the proposed model describes the fundamental unit of consciousness (as in the subject line), but for many philosophers the term "consciousness" brings along certain expectations which tend to be missing from the simplest requirements of the model.  Similarly with the term "sentience".  Therefore I have coined (I think) a new term to describe the fundamental unit.  I will then claim that any sentient or conscious event is a psychule, and leave it to future generations to decide whether the definitions of consciousness and sentience should be extended to include each and every psychule.

As mentioned, a psychule is an event.  More specifically, a psychule is a pattern recognition type of event. I use the term "pattern recognition" with some trepidation, as that term seems also to bring some unwanted baggage for some philosophers.  Nevertheless, I find the term "pattern recognition" more intuitive than "pattern discernment", so I request that readers who object to the model based on the idea of "pattern recognition" replace that "recognition" with "discernment" and determine if the objection still stands.

I will try to make this explanation of the model as simple as possible and accept the risk that the description is too simple.  There are three main characters in the model: the input, the agent, and the output.  There are additional characters in the wings, but they can remain there until called for. So now for the statement of the model:

A psychule is an event wherein a well-defined subset of the internal relations (discernible variables) of an isolated configuration of matter (the input) is recognized by an agent which then generates a second configuration of matter (the output) such that the output is at least potentially a valuable response, that value accruing not to the agent but to whatever generated the agent.

To break this down a little, we start with a defined configuration of matter which is the input and which we will call system B (because system A is a prior system which will be drawn into this discussion later).  Depending on the makeup of system B, there may be many identifiable internal relations among the parts.  For example, if system B is a baseball, the discernible variables may include leather cover, threads, weight, diameter.  Alternatively, the pertinent variables may be the presence of specific molecules at a given temperature. The description of a psychule requires only that the subset of variables relevant to the agent be specified.

The agent is also a system (isolated configuration of matter), but we'll just call it the agent.  The agent, when presented with the input (system B), recognizes the specified set of variables and responds appropriately by generating the output. Note that the process of generating the output may be very simple, such as an enzyme recognizing a specific sequence in a DNA strand and cutting it.  The process may also be very complicated, such as a short order cook getting an order for a cheeseburger then generating an actual cheeseburger.  They both count as psychules. Note also that a process similar to the enzyme example does not (necessarily) count as a psychule, namely chemical catalysis.  The pertinent difference is what is missing from the latter: generation of value.  But even then, if that chemical catalyst is intentionally arranged, as in the catalytic converters in car engines, then the event generates value and can be considered a psychule.

So the simple event can be written: B --agent]--> C, or more simply just B -> C.

So how does something as simple as a psychule pertain to something as complicated as consciousness? The answer is that psychules can be combined in series and in parallel to form larger psychules. All of the "non-exposed" inputs and outputs, i.e., not initial inputs and not final outputs, become internal to an agent.  

As an example, let's consider a simple agent X: a group of molecules embedded in a membrane where the aqueous space on one side of the membrane has many positively charged ions. When that group recognizes a molecule, say, serotonin, on the correct side of the membrane (system B), it opens a channel and positive ions flow across the membrane (system C, the output).  We write this B -> C.

Nearby, another group of molecules, agent Y1, recognizes that some positive ions have flowed across the membrane and agent Y1 also opens a channel that lets more positive ions flow across the membrane (system D).  We write this C ->D.

Nearby agent Y2 (just like Y1) does the same thing Y1 did, generating system E. This continues until system P (yet more positive ions crossing the membrane) is recognized by agent Z, a vesicle filled with, say, glutamate(?), and agent Z responds by fusing with the membrane, thus releasing the glutamate to the outside (system Q, the final output, for now).

So we write this whole chain as B->C->D->E->[...]->P->Q,

Or we could just write this:  B(serotonin) --[neuron]--> Q (glutamate). (I'm not sure if any neurons actually take serotonin and generate glutamate, but you get the idea.)

Similarly we could have three agents that respectively perform A->B, C->D, and E->F, and one agent that performs B+D+F->Q. If it's useful, we could combine those agents and we end up with one agent that performs A+C+E->Q.

Finally, you can have agents that have a repertoire of psychules that is more than just one.  For example, you could combine the three agents mentioned in the previous example such that you have one agent that responds to A by producing B, responds to C by producing D, etc.

So the bottom line for this model is that any given consciousness, or conscious agent, can be designated somewhat arbitrarily as a combination of one or more sub agents.  I say somewhat arbitrary because it is generally useful to have a reason for any particular designation, such as one particular brain, as opposed to a completely arbitrary designation, such as my watch plus this cup of coffee.  Further, the "consciousness" of any designated agent is defined by the repertoire of psychules that the agent can perform.

There is much more to discuss, but I would appreciate comments, objections, etc., to what I have presented so far.  Thanks for reading.

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