Editing Darwin's Dangerous Idea (section)

== Central concepts ==

=== Design Space ===
Dennett believes there is little or no principled difference between the naturally generated products of evolution and the man-made artifacts of human creativity and culture. For this reason he indicates deliberately that the complex fruits of the tree of life are in a very meaningful sense "designed"—even though he does not believe evolution was guided by a higher intelligence.

Dennett supports using the notion of memes to better understand [[cultural evolution]]. He also believes even human creativity might operate by the Darwinian mechanism.<ref>{{cite web| url = http://ase.tufts.edu/cogstud/papers/valencia.htm| title = Could there be a Darwinian Account of Human Creativity?| date = 28 March 2023}}</ref> This leads him to propose that the "space" describing biological "design" is connected with the space describing human culture and technology.

A precise mathematical definition of Design Space is not given in ''Darwin's Dangerous Idea''. Dennett acknowledges this and admits he is offering a philosophical idea rather than a scientific formulation.<ref>{{cite web| url = http://ase.tufts.edu/cogstud/papers/philbook.htm| title = Reply to Gregory Mulhauser| date = 28 March 2023}}</ref>

=== Natural selection as an algorithm ===
Dennett describes [[natural selection]] as a substrate-neutral, mindless [[algorithm]] for moving through Design Space.

=== Universal acid ===
Dennett writes about the fantasy of a [[alkahest|"universal acid"]] as a liquid that is so corrosive that it would eat through anything that it came into contact with, even a potential container.  Such a powerful substance would transform everything it was applied to; leaving something very different in its wake.  This is where Dennett draws parallels from the “universal acid” to Darwin's idea:
<blockquote>
it eats through just about every traditional concept, and leaves in its wake a revolutionized world-view, with most of the old landmarks still recognizable, but transformed in fundamental ways.{{citation needed|date=July 2023}}
</blockquote>
While there are people who would like to see Darwin's idea contained within the field of biology, Dennett asserts that this dangerous idea inevitably “leaks” out to transform other fields as well.

===Skyhooks and cranes===
Dennett uses the term "skyhook" to describe a source of design [[complexity]] that does not build on lower, simpler layers—in simple terms, a [[miracle]].

In philosophical arguments concerning the [[reduction (philosophy)|reducibility]] (or [[irreducible (philosophy)|otherwise]]) of the human mind, Dennett's concept pokes fun at the idea of [[intelligent design]] emanating from on high, either originating from one or more [[god]]s, or providing its own grounds in an absurd, [[Baron Munchausen|Munchausen]]-like [[bootstrapping]] manner.

Dennett also accuses various competing [[neo-Darwinism|neo-Darwinian]] ideas of making use of such supposedly unscientific skyhooks in explaining [[evolution]], coming down particularly hard on the ideas of [[Stephen Jay Gould]].

Dennett contrasts theories of complexity that require such miracles with those based on "[[crane (machine)|crane]]s", structures that permit the construction of entities of greater complexity but are themselves founded solidly "on the ground" of physical science.