Our general argument for this is based on the idea that, to evolve complex systems that still are efficient, every process of evolution must find a compromise between these two alternatives:
If a system’s parts have too few interconnections, then its abilities will be limited.
But if there are too many connections, then each change will disrupt too many processes.
How to achieve a good balance of these? A system could start with clearly distinctive parts (for example, with more-or-less separate layers) and then proceed to make connections.
Embryologist: In its embryonic development, a typical structure in the brain starts out with more or less definite layers or levels like those in your A, B, C diagrams. But then, various groups of cells grow bundles of fibers that extend across those boundaries to many other quite distant places.
Or, the system could begin with too many connections and then proceed to remove some of them. Indeed, this also happened to us: during the eons through which our brains evolved, our ancestors had to adapt to thousands of different environments—and, every time this happened to us, some features that formerly had been ‘good’ now came to function as serious ‘bugs’—and we had to evolve corrections for them.
Embryologist: Indeed, it turns out that more than half of those cells proceed to die as soon as they’ve reached their targets. These massacres appear to be a series of ‘post-editing’ stages in which various kinds of ‘bugs’ get corrected.
This reflects a basic constraint on evolution: it is dangerous to make changes to the older parts of an animal, because many parts that later evolved depend on how the older ones work. Consequently, at every new stage, we tend to evolve by adding ‘patches’ to structures that are already established. This led to our massively intricate brains, in which each part works in accord with some principles, each of which has many exceptions to it. This complexity is reflected in human Psychology: where each aspect of thinking can be partly explained in terms of neat laws and principles—but each such ‘law’ has exceptions to it.
The same constraints appear to apply whenever we try to improve the performance of any large system—such as an existing computer program—by adding more fixes and patches on top, instead of revising the older parts. Each particular ‘bug’ that we remedy may eventually lead to more such bugs, and the system keeps growing more ponderous—and this seems to apply to our present-day minds.
This chapter began by presenting a few widely held views of what “consciousness” is. We concluded that people use that word for a great suitcase of mental processes that no one yet thoroughly understands. The term ‘conscious’ is useful enough in everyday life—and seems almost indispensable for talking on social or ethical levels—because it keeps us from being distracted by wanting to know what’s inside our minds. It is the same for most other psychology-words, such as understanding, emotion, and feeling.
However, when we don’t recognize that we are using suitcase-words, then we may fall into the trap of trying to clearly define what those kinds of words ‘mean.’ Then we get into trouble because we do not have clear enough ideas about what our minds are and how their parts work. So, if we want to understand the things that human minds actually do, we will have to dissect our mental processes into parts that we can analyze. The following chapter will try to explain how Joan’s mind could do some of the sorts of the things that people can do.
Part V. Levels Of Mental Activities
“We are evidently unique among species in our symbolic ability, and we are certainly unique in our modest ability to control the conditions of our existence by using these symbols. Our ability to represent and simulate reality implies that we can approximate the order of existence and … gives us a sense of mastery over our experience.”
—Heinz Pagels, in The Dreams of Reason
No person has the strength of an ox, the stealth of a cat, or an antelope’s speed—but our species surpasses all the rest in our flair for inventing new ways to think. We fabricate weapons, garments and dwellings. We’re always developing new forms of art. We’re matchless at making new social conventions, creating intricate laws to enforce them—and then finding all sorts of ways to evade them.
What enables our minds to generate so many new kinds of things and ideas? This chapter will propose a scheme in which our resources are organized into six different levels of processes.
Beginning with simple instinctive reactions, each layer is built on the previous one—until they extend to processes that involve our highest ideals and personal goals. To see why we need many levels for this, let’s revisit the scene in §4-2.
Joan is part way across the street on the way to deliver her finished report. While thinking about what to say at the meeting, she hears a sound and turns her head —and sees a quickly oncoming car. Uncertain whether to cross or retreat but uneasy about arriving late, Joan decides to sprint across the road. She later remembers her injured knee and reflects upon her impulsive decision. “If my knee had failed, I could have been killed—and what would my friends have thought of me?”
The first part of this chapter will show how each level of this diagram could explain some of what happened inside Joan’s mind. We often react to events ‘without thinking’, as though we were driven by If–>Do rules like those described in §1-4. But such simple reactions can only explain the first few events that we see in this scene; the rest depends on activities in all those other levels of Joan’s ways of thinking.
Inborn, Instinctive Reactions: Joan hears a sound and turns her head. All animals are born equipped with ‘instincts’ that help them to survive.
Learned Reactions: She sees a quickly oncoming car. Joan had to learn that conditions like this demand specific ways to react.
Deliberative Thinking: To decide what to say at the meeting, she considers several alternatives, and tries to decide which would be best.
Reflective Thinking: Joan reflects upon what she has done. She reacts, not just to things in things in the world, but also to recent events in her brain.
Self-Reflective Thinking: Being “uneasy about arriving late” requires her to keep track of the plans that she’s made for herself.
Self Conscious Emotions: When asking what her friends think of her, she also asks how her actions concord with ideals she has set for herself.
The second part of this chapter will show how such systems could “imagine” things. Whenever you ask, “What would happen if,” or express any hope, desire, or fear, you’re envisaging things that have not yet appeared. Whenever you interact with your friends, you’re anticipating how this may affect them. Whatever you see, it suggests some ideas about possible futures those objects might bring. How could our mental resources conceive of things that do not yet exist, and then apply those new ideas to ways to change and extend themselves?