Philosophy: Deepities, cranes and skyhooks

Melvin Konner sorts through a philosopher's box of tools for the musing mind.

Intuition Pumps and Other Tools for Thinking

W. W. Norton: 2013. 512 pp. $28.95 9781846144752 9781480512207 | ISBN: 978-1-8461-4475-2

Full disclosure: I am no sort of philosopher — I am not even a 'sorta' philosopher, to use one of Daniel Dennett's favourite coinages. But I aspire to being a sorta intelligent general reader, which would make me a fair example of the target audience of Dennett's Intuition Pumps and Other Tools for Thinking. I am also more than a sorta Dennett fan: I reviewed Freedom Evolves (Penguin, 2004) favourably in these pages, and I liked Consciousness Explained (Penguin, 1993) and Darwin's Dangerous Idea (Penguin, 1996). Dennett, a noted philosopher, is one of those who take science seriously, believing that reasoning without facts can be a fool's errand. And in his previous books, he performed a service that is one of philosophy's main contributions: clarification of discourse.


For me, this is not quite achieved in Intuition Pumps. The book reads like a collection of short essays — nearly 80 chapters in 440 pages — grouped in sections loosely connected by theme. One section is a fairly conventional precis of basic ideas in computing; others explain evolution, consciousness and free will. The intuition pumps are, as the title says, tools for thinking: they are thought experiments focused on problem-solving. And although Dennett wants to help us to think with them, he dislikes many and treats them as straw men. For example, skyhooks — thinking-tools that hang an explanation on nothing — are bad. These include intelligent design, for explaining too-intricate bits of biological machinery, and divine inspiration, for too-brilliant works of art. But cranes — concepts built on a solid factual foundation — are good. Take symbiosis or sexual reproduction, which speed up the work of random, blind-designer evolution; these are concepts that give evolution a legitimate boost.

Well, yes. But are skyhooks and cranes comparable kinds of ideas? Symbiosis and sex are evolved processes like respiration or photosynthesis; each began with random mutation and, by gradual natural selection, produced a 'design' that changed the history of life. But what do skyhooks and cranes add to the basic principles of how we think about evolution? The next time I comfort a student struggling between faith and Darwin, it will not help me to say, “What you learned in Sunday school about evolution needing a 'big boost'? That's just a skyhook.” Rather, I will do what I do now: help the student to zero in on variation, inheritance, selection and, crucially, how very many generations there have been since evolution began. As Dennett states elsewhere in this book, the word for this is not 'crane' but 'algorithm' — both more and better than a metaphor.

A two-page chapter defines 'deepities', a coinage borrowed from a child, as meaningless statements that seem deep. His main example: “Love is just a word”, which Dennett follows with, “Oh wow! Mind-blowing, right? Wrong.” The idea of deepities is offered as a thinking tool to protect us from such shallow statements in disguise. But are we to find his reply to this deepity deep?

I share many of Dennett's views: a 'designed' nature without a designer; the mechanistic, emergent character of consciousness; the rejection of the homunculus argument, or the idea that an entity (often characterized in discussion as a little person) watches a theatre consisting of the rest of the brain; and the compatibility of free will with determinism. But I do not see the need to repeat arguments made less flippantly in earlier books. An artfully selected Dennett anthology would overlap considerably with this one, and might be easier to follow.

There is quite a bit of score settling. Dennett takes issue with thinkers ranging from Robert Beverley MacKenzie, who in 1868 called Darwin foolish for believing in designs with no designer, to evolutionist Stephen Jay Gould, who died in 2002, and the philosopher John Searle, both of whom Dennett has often censured.

Gould, for instance, found nature full of biological traits that he did not consider were in themselves adaptations, and hated what he called 'Panglossian adaptationism', or what he saw as the overly optimistic explanatory efforts of much recent Darwinian thinking. He used the evidence for punctuated equilibrium — long stretches of stasis in fossil records interrupted by change — to suggest a need for revising Darwin. Yet the 'punctuations' were easily long enough for natural selection. Even so, I fail to see what is gained by Dennett's coining a verb, goulding, to denote certain logical errors. Gould's research is valued; he was also a fine science communicator and a spirited defender of evolution.

Dennett says that although philosophers would rather be clearly right than clearly wrong, many would most like to be confusing, because confusing things endure in reprints and homework. He admits to abetting that process by engaging with the work of those he criticizes. But I fail to see the point of keeping bad ideas famous with reiterated arguments; perhaps that is why I am not a philosopher. I look forward to Dennett's next book, which I hope will be something ambitious: Evolution and History perhaps, or How the Brain Decides, or maybe Philosophy as a Science. But it is not for me to put a title in his laptop. I just hope that it reminds me more of his earlier, grander books, so that I can turn to it on my night table, once again a delighted Dennett fan.

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Correspondence to Melvin Konner.

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Konner, M. Philosophy: Deepities, cranes and skyhooks. Nature 497, 184–185 (2013).

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