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Constructing the Mind

dshanin's picture

In Darwin’s Dangerous Idea the contemporary philosopher Daniel C. Dennett uses a serious of metaphorical constructs in order to fully explore the many facets of Darwin’s theory of evolution. One of these devices is the skyhook and the crane. A crane represents a theory built of our own world’s rules and set in a foundation of the real while a skyhook is a by-definition impossible floating hook. The skyhook is anchored in another world and reflects the different set of rules and beliefs associated with that alternative world. In short, a crane represents the non-foundationalist beliefs that are built on a base of chance and luck while the skyhook represents the foundational, non-corporeal framework by which earthly actions are evaluated. As Dennett shows, these constructs are useful for the evaluation of Darwin’s teachings but their applicability expands far beyond realm of evolution. Through the use of the skyhook and crane conventions it is possible to explore difference between the competing “truths” of non-foundationalism and foundationalism as well as the distinction between mind and brain. This will allow us to question the very nature by which the human brain, the peak of a crane, possesses the mind, which creates all skyhooks.

Cranes are firmly anchored in the hard soil of our world yet they are not built towards any eventual goal; rather each small increase in the height is the result of “brute, mechanical, algorithmic” forces (Dennett, 75). When applied to evolution, these small steps are the generation upon generation of minute variation acted upon by natural selection. Every currently existing organism is the top of a crane with its ancestors nestled below it. As this definition suggests, Dennett’s cranes do not need to be linear. Many current species come from common ancestors, or in terms of the metaphor, the same underlying crane. This poses a serious issue in terms of our ability to visualize the metaphor as many thousands of cranes rising out of a single one is rather difficult to imagine. The solution comes by narrowing the focus, instead of considering all cranes at once, the model is better utilized to explore each crane individually from the top (or current manifestation) downward. By doing this, the location of adjacent cranes becomes less important than the mere existence of a continuity of steps leading all the way down to the ground. This stepwise nature of a crane is key to its non-foundationalist ideology. There is no ultimate goal, up is not better or closer to perfection than down; it simply represents a more recent event in the chronological progression.

The skyhook, by contrast, is a “mind-first” process. Though anchored in the sky of our world, it is planted firmly in the soil of another world. Dennett frequently uses religion as an example of a skyhook. Western religions follow a moral doctrine that is viewed as universal. The doctrine simply is; there was no gradual randomized process to build it, instead all that occurs on our world can be viewed in terms of how close it comes to meeting the ultimately unachievable goal. By placing an intangible roadmap upon our perceivable world the skyhook is the very definition of foundationalism. While Dennett is not totally anti-skyhook he does view the theory of evolution’s greatest strength as its reliance on cranes alone. It is not the skyhook itself that is erroneous but rather when skyhooks are attributed the same level of reality as cranes and serve as the basis for an entire belief structure (as in religion) that Dennett feels they weaken an arguement.

When viewed a crane, as Dennett suggests it should be, the theory of evolution gets very interesting at the extreme top and bottom. As Dennett points out, “Darwin came up with some magnificent cranes to do the middle-level lifting” but the real question raised by evolution is how to “get the booms of Darwin’s cranes off the ground in the first place”. (Dennett, 155) The beginnings of life are the most controversial part of the theory of evolution and the part least satisfactorily covered by Darwin. Modern research has suggested that virus-type macromolecules arose which, through chance and over great periods of time, acquired the ability to aggregate raw materials into themselves. Eventually these molecules gathered biological molecules from the environment, these early clumps of crystals, amino acids and nucleotides gradually became able to add to themselves. The truly astounding step occurred when the nucleotides began to represent parts of the molecule other than themselves (contain information). Modern biology holds that a unique combination of this pre-biotic “soup” and energy provided from lightening and volcanoes was able to catalyze this great event. Thus even though we have no direct evidence of the creation of life (other than life itself), Dennett confidently views it as “no skyhook – just a ladder that could be thrown away” (Dennett, 158).

Just as in the evolution, the most interesting parts of the idea of cranes are the very top and bottom. When asked what the bottom of a crane is anchored in it is easy to say “our world” but defining what that actually means is another issue all together. All of the things that define our lives; humanity, society, even the geology of earth are all the peaks of cranes stretching back further than we can comprehend. If we follow these cranes back to their foundations where do they lead? In the physical sense you could trace all of these things in our world back to the birth of our planet; when a disk of leftover material from our sun’s formation slowly condensed into the planets and moons but this a concrete answer for an abstract concept. Rather, the cranes are based in a world where we recognize and universally share the same rules. Opinions and perceptions differ but at the bottom of it all there must exist a truth so pure that there can be no differences; an absolutely solid foundation upon which our cranes found the support they needed to tower as high as they do.

The use of “truth” to describe the base of the non-foundationalist crane is a seeming contradiction in that “truth”, or perhaps “Truth”, is the central dogma of a skyhook. The crucial difference between these truths is where they come from. The non-foundationalist truth of cranes is the result of the distillation of everything in our world to an original singularity while the Truth of skyhooks represents an unachievable ideal as put forth by a human mind. The human mind is crucial to the skyhook; without one the other cannot exist. This raises the ultimate question, one that calls the entire model into question; if the human brain is the top of one of the tallest cranes; how can the human mind it contains create a skyhook? The space separating the crane and the skyhook represents the fundamental leap between our world and another. In terms of humanity this jump is the difference between the brain (crane) and the mind (skyhook). This gap does not weaken us, as Dennett suggests, but rather underlines the incredible abilities of the human mind and the unbelievable height that the cranes of evolution have reached. The human brain itself is just a conglomeration of neurons and glial cells, similar in layout (save for a decidedly larger cerebral cortex) to those of most other creatures on earth. Yet some critical boundary was crossed as the crane of human evolution built slowly upward, a structure evolved, wholly based in the non-foundational randomness of our world, that could independently create an unlimited number of its own worlds. In Dennett’s metaphor, height is everything, and the ability of the human mind to reach new worlds in instants is the truly defining factor of our humanity. A crane from our world reached high enough to seed an uncountable number of alternative words, each wholly contained within a mind, but each just as important (and real to itself) as the one upon which our own cranes are based.


Paul Grobstein's picture

cranes and skyhooks: the every bottom and very top?

"at the bottom of it all there must exist a truth so pure that there can be no differences; an absolutely solid foundation upon which our cranes found the support they needed to tower as high as they do"

Perhaps this thought results from thinking like a skyhook?  Why must there exists such a truth?

"some critical boundary was crossed as the crane of human evolution built slowly upward, a structure evolved, wholly based in the non-foundational randomness of our world, that could independently create an unlimited number of its own worlds"

Yep, a skyhook, but perhaps built slowly, like a crane, so there's no "critical boundary"?