The human mind is that part of the brain that is able to imagine, and exists mostly in the forebrain. That is why the foreheads of modern people do not slope backwards as in other primates. This forebrain was probably previously the organ of smell, which for our species uniquely, has evolved in a truly remarkable way. Imagination and communication are so closely related that it is reasonable to aver that the principal purpose of language is really to tell lies!
We will have much to say about the mind, memories and thinking, so these terms should first be defined. It is reasonable, for our purposes, to say that the myriad of neural networks of stored information that we call memories, when considered together, form what we might call a “quiescent” mind—a mind that is ready to handle information, but is not actually doing so. (A person with such a mind would be called “brain dead,” and the kind and amount of information that such a “mind” might be reactivated to handle would vary greatly with circumstances.) An “active” mind would be one where chemical ion flows are carrying information from place to place. All living minds are constantly active.
The term “memories” includes all of an individual’s mentally stored facts, theories, opinions, personal experiences, recallable emotions, past thoughts, ideas, etc. “Thinking,” for most of our purposes, can be defined as the act of seeking relationships between these memories, or between memories and current stimulations being received from body sensors. (What occurs during thinking is examined more thoroughly in the next section.)
Animal behaviour studies suggest that many animals possess rudimentary thinking abilities. Tool making is considered to be evidence of the ability to think and many creatures make and use tools. Racoons pick up and use stones to break open clams. Beavers not infrequently shape wood as they construct dams to hold water to store and preserve food they need during winter. Chimpanzees use rocks or heavy sticks to crack open hard-shelled fruit and nuts; they also fashion drinking cups and rain-sheltering umbrellas from banana leaves, and use sticks to extract insects and grubs from small holes. Birds also make and use tools.
Many animal behaviourists contend that their studies demonstrate animals can think. Hausser declares that animals think, but simply lack the ability to express their many thoughts and emotions to others. Calvin states that animals can assess their environment, consider alternative actions and make decisions—all necessitating the ability to think. That animals can think implies that thinking, like every other biological feature and process, has evolved over the ages. Thinking certainly did not suddenly spring, fully formed, into existence in humans.
The specific content of any mind (animal or human) is currently hidden to investigators because the mind functions only when neural networks are biochemically or electrically activated, and, to date, scientists have no technique precise enough to find out just which memories of the multitude locked in the brain’s neural patterns are being activated at any particular instant. Nevertheless, neural networks are real; they can be seen (and photographed as they develop) increasing in complexity as infants age and learn. (The increasing complexity of an adult’s learning brain is hidden within, and masked by, its multitude of existing neural pathways.) The biochemical flows that retrieve and carry information stored within these neural patterns is also real. In short, neural networks whose paths store memories within the brain constitute the mind, and thinking depends upon biochemical flows activating some or many of these networks, so releasing (and making available for potential use) the information they hold.
- See Andrew Whiten and Christophe Boesch, “The Cultures of Chimpanzees,” Scientific American, January 2001, 61-67, for intriguing descriptions of chimpanzee behaviour. Neighbouring communities of chimps apparently occasionally battle each other to the death. (Ah! Perhaps we can blame a common ancestor for contributing the same trait to us.)
- Crows in the New Caledonian rain forest are as advanced in their ability to use tools as were Stone Age humans. The birds strip bark from a twig, cut the twig just below an offshoot to create a hook, and then insert this hook into tree cavities to remove insects and larvae. They also use a barbed type of leaf which they peck into a tapered point for similar functions (showing a left-handed preference when tailoring pine needles). They make several different types of tools, each for its own specific purpose, and even produce tools in assembly line fashion—that is, they finish a number of tools before using any of them. Man did not reach this stage until the Lower Palaeolithic era, 2.5 million to 200,000 years ago. Readers with an interest in the intelligence of birds, crows in particular, will enjoy Bernd Heinrich’s book, Mind of the Raven: Investigations and Adventures with Wolf-Birds (New York: Harper Collins, 1999).
- Marc D. Hauser, Wild Minds: What Animals Really Think (New York: Henry Holt and Company, 2000), 209.
- Hauser, 257.
- Calvin, The Ascent of Mind, 24.
- However, Wilder Penfield, in his experiments that electrically stimulated points within the brain, may have been close to finding out. (This kind of investigative work is considered unethical and is not practiced today.)