On the rise of recursion Discussion

The analysis of recursion has triggered considerable debate on the ontological status of this phenomenon. One of the issues raised concerns its status vis-à-vis language, where the following views in particular have been expressed:

(a) Recursion is essentially language-based. Fitch, Hauser, and Chomsky (in press: 19) argue that there are no unambiguous demonstrations of recursion in other human cognitive domains, with the only exceptions (mathematical formulas, computer programming) being clearly dependent upon language. Pinker and Jackendoff (2005: 230) believe that recursive number systems, though not other recursive systems, may have been exapted from the recursive properties of language (see below). But assuming that recursion is language-based, where exactly is it located? (i) Is syntax the locus of recursive structure, as is maintained in much of the generative work, (ii) are syntax and semantics parallel recursive systems (Jackendoff 2002), or (iii) is semantics the source of recursive structure? On the basis of the circumstantial evidence that is available, no definite answer seems possible.

(b) Recursion in language is derivative of other cognitive abilities. Pinker and Jackendoff (2005: 230) argue that the only reason language needs to be recursive is mental: ‘‘If there were not any recursive thoughts, the means of expression would not need recursion either.’’

(c) Recursion occurs independently in different cognitive domains. Hauser, Chomsky, and Fitch (2002: 1569, 1578) consider it possible that their FLN evolved for reasons other than language and that if ‘‘recursion evolved to solve other computational problems such as navigation, number, number quantification, or social relationships, then it is possible that other animals have such abilities’’, and that key computational capacities evolved for reasons other than communication but, after they proved to have utility in communication, were altered. But this view is controversial. For example, as Pinker and Jackendoff (2005: 230) point out, the two principal navigation systems documented in non-human animals do not show the discrete infinity of recursion: Dead reckoning is infinite but not discrete; recognition of landmarks is discrete but not infinite.

There are a number of other issues that are still ill-understood. One concerns the question of whether recursion is innate and/or neurally based (e.g. Calvin 2005: 8) or whether it evolves via cultural transmission (Kirby 2002). Hauser, Chomsky, and Fitch (2002: 1574) observe that recursion is implemented in the same type of neural tissue as the rest of the brain and is thus constrained by biophysical, developmental, and computational factors humans share with other vertebrates. Deacon (2003: 129) on the other hand points out that an evolved innateneurally based recursive processing faculty is both unnecessary and unsupported by the evidence, in that ‘‘the formal recursion that symbolization allows in the external form may nevertheless be processed in non-recursive ways neuro logically’’. And he concludes that the implicit affordance for recursion that symbolic reference provides can be expected in any symbolic system.

Another issue that needs to be addressed is whether there are significant stages or degrees in the recursive ability. There is a view that one either has the idea of nested embedding or one does not, and if one does, one can carry it to considerable depths—that is, that recursion is an all-or-nothing phenomenon (Berwick 1998; Calvin 2005: 6). Conversely, we drew attention to the distinction between simple and productive recursion and the relevance it has for linguistic typology. More research is required on this issue.

Finally, there is a problem that we have already alluded to above, namely one relating to the status of the recursive mechanism of succesion and of numerosity in general. Numerical cognition has been analyzed as being closely linked to language—either as being bootstrapped or inferred from language in development or as being derivative of language (Hurford 1975, 1987). Arguing that those human cultures that have developed recursive number systems in their cultural history may have exapted them from the recursive properties of language, Pinker and Jackendoff (2005: 231) conclude that ‘‘recursive number cognition is parasitic on language rather than vice-versa’’. And based on an extensive analysis of number and number systems, Wiese (2003) argues that we do not have to look for an independent development of recursivity outside the language system.

On the other hand, numerical cognition and language are also claimed to belong to different and independent mental faculties. The following observations in particular suggest that succession is independent of other recursive mechanisms, and of language in general (see Gelman and Butter-worth 2005; Grinstead et al. n.d. for details):

(a) Considering their different nature, it would be hard to establish for example that rules underlying embedding recursion move from syntax to numerosity.

(b) Some mentally retarded individuals who demonstrate intact grammatical development nevertheless possess limited or no ability to calculate and have little grasp of basic counting principles.

(c) Some hearing-impaired adults who have developed no grammar in the sense of natural human languages never the less are able to use number.

(d) There is crosslinguistic evidence to the effect that speakers of languages having no recursive number system, lacking the ability to count, such as the Pirahã of Amazonia, !Xun of Namibia, or Warlpiri of Central Australia, are nevertheless able to learn and handle such a mechanism in arithmetic tasks (see e.g. Gelman and Gallistel 2004: 441).

اخر الاخبار

اخبار العتبة العباسية المقدسة

العتبة العباسية المقدسة تسدل الستار على الختمة القرآنية الرمضانية المركزية المرتّلة

العتبة العباسية المقدسة تنظم برنامجًا ثقافيًّا لوفد من الطلبة العرب والأجانب في جامعة النهرين

شعبة الخطابة النسوية تختتم برنامجها الرمضاني (قوارير في ضيافة الله)

العتبة العباسية المقدسة تكرم الفائزين في مسابقات ملتقى النورين الخامس والمساهمين في إنجاح فعالياته

المزيد

الآخبار الصحية

كوب قبل النوم.. مشروب طبيعي يحارب الأرق

دون أدوية.. طريقة طبيعية لخفض ضغط الدم بفعالية مذهلة

المعكرونة ليست عدوك.. كيف تصبح جزءا من وجبة صحية متوازنة؟

دراسة: تناول القهوة يوميا يخفض خطر الإصابة بالاضطرابات النفسية

المزيد

الآخبار التكنلوجية

علماء روس يخططون لبناء منشأة للكشف عن المادة المظلمة

ثاني أكسيد الكربون ليس تهديدا للمناخ فقط.. بل لصحة الإنسان أيضا!

ديدان الأرض تكشف تلوث التربة بالمعادن الثقيلة

خبير أرصاد جوية: ظاهرة النينيو القادمة قد تكون الأقوى خلال 10 سنوات

المزيد

مواضيع ذات صلة

Animal cognition

Are there languages without recursion?

Treatment of recursion in linguistic description

Embedding, iteration, and succession

Simple vs. productive recursion

Manifestations

What is recursion? A definition

What is recursion?

On the rise of recursion

Case study: be going to

The subjectification approach

Case study: the evolution of must