Chapter 10
Sensory and Cognitive Limitations
Most humans have five senses – Sight,
Hearing, Touch, Smell, and Taste. Lack of any of these is typically referred to
as a “handicap”. Some claim to have a sixth sense – an extrasensory perception
that includes Telepathy, Clairvoyance, Precognition, and Psychokinesis. Let’s
table our ESP discussion for a future chapter.
In recent years, scientists have
suggested that we add more senses to our base-five. Proprioception is
our sense of our body position in space. Equilibrioception is our sense
of balance. Thermoception is our sense of temperature. Nociception
is our sense of pain. Interoception is the sense of our internal body
state. We could list more. However, for the sake of this discussion, let’s
stick with the five traditional senses that were classified in the days of
Aristotle.
Our knowledge of the world is gained
through our senses. Limitations of them, constrain our accumulation and storage
of knowledge – vital to our survival. We’ve already discussed how the
information we receive from others – Influencers - vary greatly in quality. For
that matter, how did these people gain their own knowledge? At some point, all
knowledge derives from the human senses. Even theoretical knowledge is
considered a “guess” until it is proven by observation, which uses our senses.
Hence, the quality of human knowledge is dependent on the quality of our
senses. So, to further support my assertion that we can know almost nothing
with certainty (Don’t despair. I’ll get to the stuff our egos will like in due
time), let’s run through the limitations of each of our five primary senses.
Sight/vision:
For most of us this is our dominant sense. However, humans can only see a small
fraction (.0035%) of the electromagnetic spectrum – visible light. We require
special instruments to detect ultraviolet light, infrared radiation, X-rays, or
radio waves. Humble bees and snakes can detect parts of the light spectrum our
eyes can’t. Even humans with “perfect vision” can’t see beyond a short
physical distance before they lose detail. Dim the lights, and we are all in
real trouble. Sleight-of-hand magic is faster than our eyes can follow. As we
age, our limitations can become even more problematic. (As I type this passage,
I squint through my tri-focals.)
Hearing:
Like vision, we require technology to hear outside our narrow range – roughly
between 20 Hz and 20,000 Hz. We can’t hear the low rumblings of an earthquake
or the high-pitched communication of bats. As we age? I wish I could hand the
17-year-old me earplugs as he leaned against Hendrix’s speakers. For me,
Jimi’s feedback is more than just a memory.
Touch: We feel pressure,
temperature, pain, and texture. But we can’t detect microscopic changes without
modern tools. Our elbows lack the sensitivity of our fingertips. Our perception
of pain is subjective. It is influenced by factors such as emotions, context,
and our upbringing.
Taste and Smell:
As you know, these last two senses are connected. They are also extremely
limited. A dog’s sense of smell is thousands of times more sensitive than our
own. Our taste receptors are limited to sensing sweet, salty, sour, bitter, and
umami.
You might argue that we have sufficient
senses to survive as a race. Up to a point, I would agree. Further, with our
mental capacity and dexterity, we have greatly extended the reach of our perceptions.
Scientists use microscopes, telescopes, sensors, and imaging systems to extend
our awareness well beyond our physical limitations.
Life comes at us quickly and we rarely
have time to fish out a pair of binoculars to see a charging rhino, yet we’ve managed
to survive. How? Herein is our blessing and our curse. Our brains quickly fill
in gaps of knowledge by making best guesses as to what we are encountering
based on past experiences and beliefs and then adjust the predictions based on
subsequent sensory input in an attempt to reduce prediction errors. However,
the cost of efficiency is that we tend to jump to conclusions that may be
wrong. We can see these mistakes, for instance, in illusions, weird beliefs, anxiety,
depression, chronic pain and/or fatigue, and psychosomatic problems.
Now that we’ve described our sensory
(input) inferiority to many species in the animal kingdom, let’s touch on our
cognitive (processing) strengths and weaknesses.
Cognitive Limitations
Humans have built cities, cultures, and
technological wonders. We have knowledge about subatomic particles and the far
reaches of space. Yet (at the risk of pushing another buzz kill) we have definite
cognitive boundaries. In Chapter 13, we will explore our Cognitive Biases.
These are the mental cheats we employ to help us survive a hostile world that doesn’t
forgive our lack of knowledge or response time. There are also flaws in our Memory,
which we will explore in Chapter 14. And of course, we can’t forget Paul
Simon’s wise words – “Still a man hears what he wants to hear and disregards
the rest”. So, our sense of hearing is impacted by our cognitive receptivity to
the offerings of others.
Along the same line, human cognition is
impaired by Emotional and Social influences. When we are angry, anxious,
or grieving it becomes difficult to think matters through rationally and
logically. And when peer pressure is a factor, our judgement can be crippled.
There are two final limitations worth
noting. First, our attention span is finite. We can only focus on a
limited amount of information in any given moment. We are poor multi-taskers.
The best amongst us primarily possesses faster switch times. When we focus on one
area, we tend to miss changes in another. This is another deficiency that magicians exploit.
Finally, there is a limit to our powers of Processing and Comprehension. The average human struggles to understand complex
ideas like abstract reasoning, higher realms of math, and counterintuitive
scientific concepts. Our difficulty with probabilistic thinking can lead us to
misunderstand data and, consequently, make poor decisions.
What can be done to improve our
abilities? Quite a bit. We’ll leave that discussion to Part VI.
Are you still with me? I’ve got a
golfing buddy who claims to avoid reading books that focus on human
limitations. Too depressing, he claims. In my defense, in this section, we are
setting the parameters of our strengths and weaknesses. If we are to survive as
individuals and as a species, we must have an honest inventory of our assets
and deficits. Otherwise, we are striding into the Sahara with a half-full canteen. Despite shortcomings, I believe we have sufficient gifts to thrive. Let’s continue our inventory by examining other aspects of our mental states.