Description of a Person’s World
Our keyhole view of external reality (Figure 3.1) defines the initial constraint on our internal worldview, our mindset. First, our senses are sensitive (pick up) only part of the local reality. Second, we only see, hear, smell, taste, and touch objects and events which are within close proximity. Third, only keyhole information is available to be ranked in importance by our needs, desires, and fears. Lastly, only those intermediate results are arranged by our knowledge and learning into related pieces of information.
Of course, we assume the rest of reality, that part we don’t experience, is similar to the part we do.
Why is it important to discuss the keyhole perspective? It is a fundamental constraint which makes assumptions necessary to complete our working internal worldview.
Human Sensory Apparatus
Obviously, we can only sense what our sensory organs can detect. We see, smell, touch, taste, and hear things which are scaled to our sense organs.
We don’t see ultraviolet light because our eye’s rods and cones aren’t sensitive to them. We don’t hear the dog whistle that is blown by our next door neighbor.
Sensory perception is enhanced as it travels further into our cortices, in paths towards the executive areas in the frontal lobe, passing through memory amalgamation. Objects are resolved to finer detail, increased relation to our bodies, and then to past situations. Water is wet, due to its properties in relation to our size. That is the manner in which Protagorus’s “Man is the measure of all things” should be understood.
Although the external physical world is complete and connected, our knowledge and ability to understand its totality is limited by our individual point of view. We don’t know what’s happening across town of our own sensory experience, when we are at home. If we’re using headphones to listen to a favorite podcast, we cannot hear the blue jay chirp outside. Our sensed physical world is not drawn from all reality but limited to the fragments that we personally experience.
By personal experience, I mean the effect events have on us rather than the partial view we have of them.
If we never prepare the food we eat, kitchen appliances will be a mystery to us. We won’t have the mental apparatus to appreciate the food preparation effort.
The phrase “born with a silver spoon in his mouth” nicely catches the recognition that habitual early experiences will shape one’s internal view of the world. The person expects advantages that have been inherited rather than earned.
Without the mental categories, we can’t use understand, organize, or respond to the world properly. For instance, if our parents never talked about feelings and never settled arguments, we will grow up without words and behaviors to address the challenges we can face in our relationships. With a different family, a different experience, we could develop such skills. It was not the genetic facility was missing. It was the proper experience was missing.
Continual Demand from Environment
Despite our particular, limited perspective, the sensory volume is still immense. An estimated 100 million signals arrive at the base of the brain every second from the spinal cord. The neurons in the brainstem do a yeoman job, reducing that number down to 30−100 signals that require further processing in higher sections of the brain. Even for senses that arrive from cranial nerves, such as the eye, elimination of detail occurs. Each eye has 125 million rods and 7 million cones that are compressed into just 1 million signals that travel down the optic nerve to the cortex’s occipital lobe. Similar concentration of raw sensory data occurs for the other sensory organs that travel by cranial nerves to the brain.
A new stream of sensory data arrives almost continuously. Yet, we must detect dangers and opportunities in our surroundings when they are current, so we can act promptly. A quick,natural procedure is at work—grouping data into useful categories. As you will see, the Almost Gate and abstraction, is good, but not a perfect solution. Although it is fast, mistakes can and are made. Still, decisions must be made and often quickly. So its results, not logical deduction are used.
We automatically categorize sensory data. It is an unconscious, inductive process. As it is not under our conscious control or attention, it does not use words. It is not logical. It is associative.
A complete set of sensory information is not required for us to perceive an object. Perception is not complete at the first neural threshold encountered. They are multiple steps, involving multiple abstractions. Multiple simplifications allow comparison to remembered categories that do not require exact matches to incoming sensory data. We ‘see’ a complete dining room table although the far side may be partially hidden by a huge centerpiece. We recognize friends despite differences that may exhibit on any particular day. Both occur. Abstract comparisons are supported by our neural brain as common concepts that follow the same neural path.
Induction compares en toto the incoming information to remembered categories (see Induction and Analogy). A match is detected, not when 100% of all features are identical, but when a large subset of the current information matches a remembered category. The Almost Gate, a manifestation of the necessary matching, is derived from the neural threshold and its All-or-None firing.
Induction operates in two main modes, depending on the category.
- Assignment to a remembered category despite missing or extraneous data points.
- Assignment to a more abstract category, as a set of specific information to a more general category. From observations of a relationship between specific instances, we treat all instances of the category as though they will obey the same relationship. It’s a quick assumption; unfortunately, sometimes the assumption is wrong.
Induction is the native operation of neurons. It’s fast. It abstracts. It categorizes, but it’s not exact. Those features will be developed further, along with their effects in Neural Connections.
But first, let’s continue with the effect of our genetic makeup.