The last few hundred years have seen an abundance of scientific metaphorsâincluding the medieval concept of the Book of Nature, Darwinâs natural selection and the curved space of Einsteinian physicsâand this is a tendency that continues until this day, in spite of the efforts of the logical positivists and others. This section provides an overview of metaphorical use in scientific discourse, focusing in particular on the question of how metaphorical language can perhaps influence the direction taken by scientific researchers and on how metaphor lies behind much scientific terminology.
1.2.1 Metaphor in Scientific Discourse
Interestingly, nowadays, the important role of figurative language and thinking in science is for the most part even acknowledged by writers from whom a highly cautious attitude to such matters would be expected:
Metaphors and analogies are essential to science and theory. Complex and more abstract areas of science rely particularly on metaphor and analogy to add clarity to knowledge and to communicate that knowledge. This is perfectly legitimate and indeed, to some extent, unavoidable. In science, analogies and metaphors may emerge as useful ways to think about, describe, and explain objective facts and evidence. For example, psychologists have employed the metaphor of visual selective attention being like a âspotlightâ illuminating the relevant information out there in the world from the surrounding darkness of all that we ignore. In many respects this has proved a very fruitful metaphor guiding thinking in this area of study. The problem here is not the use of analogies or metaphor in scientific thinking, but the clear abuse of them.
The problem with pseudoscience is its use and over-reliance on metaphor as an argument in and of itself. Rather than employ metaphors and analogies as illustrations of scientific knowledge, pseudoscience employs analogies to deduce new conclusions and propose alternative truths. At this point it no longer becomes a mere illustration; it becomes an argument by analogy (or metaphor âŚ).
(Braithwaite 2006)
It should be noted that Braithwaite argues that metaphor and analogy are sometimes needed in order to add clarity. Of interest here too is the distinction that he draws between science and pseudoscience in terms of their use of metaphor and analogy. The fact that this article was originally published by an organisation called UK-Skeptics means that the appraisal that it offers is likely to be a relatively sober one.
Mithen similarly identifies the use of metaphor and analogy as one of three critical properties of science (1996:245). However, it seems highly probable that the level of metaphoricity varies from one area of science to another. Dunbar, for example, argues that metaphors occur most frequently in texts about physics and evolutionary biology, with the reason being that the subject matter of these disciplines concerns phenomena âthat everyday experience does not equip us to talk aboutâ, unlike that of chemistry or anatomy, for example, for which the âconventional mechanistic terminologyâ of everyday language is totally appropriate (1995:142). Dunbar also argues that such metaphors tend to use the social human world as their source domain (1995:142; see also Mithen 1996:308). Some brief comments will be made in Section 1.2.4 regarding how popular science texts differ from specialist ones in this respect.
Finally, it should be pointed out that some metaphors become very central to our way of thinking and speaking about certain subjects, which means that, if the time ever arrives when these metaphors come to be considered obsolete, a certain realignment of concepts and means of expression will become necessary. This is the case with evolutionary biology, very central to which has always been a metaphor originally suggested by Darwin himself in The Origin of Species: âThe affinities of all the beings of the same class have sometimes been represented by a great tree. I believe this simile largely speaks the truthâ (Darwin 1872:129). Darwinâs original vision was of the totality of life on earth represented by a tree, each branch of which was a single species, some of which reach an eventual dead end but othersâtodayâs surviving speciesâextend until the very top. This image has supplied several generations of scientists with not only a fundamental âunifying principle for understanding the history of life on Earthâ (Lawton 2009:34) but also with an ultimate aim in the form of the eventual faithful reconstruction of the tree itself.
However, this view has been gradually dismantled as we have improved our ability to read genetic material and, ultimately, entire genomes. In 1999, Doolittle made the provocative claim that âthe history of life cannot properly be represented as a treeâ (1999:2124). Clearly, the Tree of Life does not exist in nature, but it is rather imposed on nature as a framework for classification (see Lawton 2009:37). If species do not simply pass on traits but also regularly exchange genetic material or hybridise with other species (as it appears that they do), then what emerges is not a âneat branching patternâ so much as an âimpenetrable thicket of interrelatednessâ (2009:36). While the model that it represents has probably not yet outlived its usefulness when applied to animals and plants, in all likelihood it no longer provides an adequate description of the workings of evolution in general; like Newtonâs mechanics, it has proved to be revolutionary and highly fruitful in its time but probably can no longer account for the highly complex data that is now being observed and discovered in the real world (see Lawton 2009: 38â9).
In addition, notwithstanding these assertions by writers such as Doolittle and Lawton, the concept of the Tree of Life is still very much alive in micr...