This chapter consists of a transcription of a fictitious forum discussion in which a number of fictitious scholars participated, including some very surprising participants. The wide-ranging discussion covers the topics discussed throughout this book, and the chapter ends with the conclusion that the nature–nurture debate is still a vibrant one in which we are seeking to understand the interplay between the nurturing experience and the role of nature, whether in the form of an innate biological endowment or in the form of natural factors that go beyond the realm of the human mind.

In this chapter, we look at a number of disciplines that study human behavior, noting that the nature–nurture issue plays a central role in all of them, albeit leading to divergent views and controversies. I select some key disciplines, making no effort to be complete. My main goal is to show that every study of human behavior inevitably asks what the roles are of innate factors and of a variety of environmental factors, and how they interact. In all cases, we find defenders of more nativist/rationalist and more empiricist approaches. I will reiterate that this debate is not only relevant to academics: Views on the roles of nature and nurture have a direct impact on many aspects of daily human life. All people will sooner or later have to take a stance on issues that concern their own lives or the lives of others, including their children, parents, or friends. It is important to see how views that different people hold with respect to, for example, education and equality, are ultimately dependent on how they think (often subconsciously), or what biases they have, about human nature and human diversity.

In this introductory chapter, I will outline what this book is about and aims to achieve, which is to continue what I started in a prequel book, A Mind for Language: An Introduction to the Innateness Debate (ML). Both books share the same central theme, namely the so-called Innateness Hypothesis for language, which is the conjecture proposed by the linguist Noam Chomsky many decades ago that children acquire language guided by an innate, genetically based mental system that is specifically dedicated to this task. Both ML and this book critically examine the arguments that have been used, or could be used, to support this idea. Where ML considered arguments coming from linguistics proper, the present book delves into arguments from neighboring fields that overlap with linguistics in various ways, including cognitive science and neurolinguistics. The chapter concludes with a review of the linguistic arguments in support of Chomsky’s innateness hypothesis that formed the focus of ML.

In this chapter we discuss a shift in Chomsky’s thinking about the extent to which the acquisition of language is based on a language-domain-specific innate system. The initial idea was that children develop their mental grammar based on two factors: a “richly articulated” innate system, called Universal Grammar (UG), and the language input. Chomsky later decided that the innate language faculty can be reduced to a single operation, “recursive Merge.” This made it necessary to acknowledge a third category of factors that plays a sizeable role in the emergence of mental grammars. These third factors cover a mixed bag, including “general learning systems” (those that empiricists would always have emphasized) and another kind of factor, which Chomsky finds more interesting: “natural laws of form” that are grounded in the laws of physics and perhaps ultimately in mathematical principles. We will discuss this notion of third factors, and I will show that attempts to explain the structure of human mental faculties in terms of principles that determine much, if not everything, in the natural world (both mind-internal and mind-external) are widespread and have a long tradition.

If some human trait or capacity is innate, it would seem that there is a genetic basis for it. This chapter explores this possibility with respect to language. We start this chapter with some genetics basics, and we will learn that there is a basis for saying that the human capacity for language has a genetic grounding, although exactly what this meansy is not so easy to establish, because the relationship between the genome and specific aspects of human mental abilities and behavior is very complex. One thing is certain: There is no (single) “gene for language.” Evidence about which genes have an impact on language often comes from people whose language abilities show certain atypical characteristics that are assumed to have a genetic basis when no other conceivable cause seems to be involved. A very important topic in this chapter is epigenetics, which is the science that studies how environmental factors can impact gene expression. This mechanism may hold the key to how nature and nurture interact in general, and the lesson to be learned is that these two factors do not compete or work independently. Rather, they are two sides of the same coin.

This chapter discusses a major contribution that Noam Chomsky made to the study of human language, which was to consider human languages in terms of generative, formalized rule systems, i.e., a formal grammar. Chomsky established a hierarchy of grammar types that differ in their so-called generative capacity, which allowed him and others to locate what kind of formal grammar within this hierarchy is needed for human languages. This hierarchy also proved useful in defining the grammars that are needed for computer languages or “languages” of nonhuman species (or even imaginable artificial or mathematical “languages”), and thus found applications in many other areas. We will ask what kinds of formal grammars can be taken as models of the mental grammars that language learners construct, considering recent developments in both formal language theory and the theory of natural language syntax. We will see that the field of formal language theory is a vibrant area of linguistics that continues to develop new methods and applications not only to syntax, but also to phonology. We will also ask whether formal language theory sheds light on the hypothesized innate language capacity.

All animal species seem to have some sort of communication system that is (largely or completely) innate. What is the nature of such systems? We will only have space to look at a few examples, which will show that some species use very complex systems. We can then ask, assuming that the human language capacity consists of several cognitive submodules, whether it is the case that some of those modules are shared with the innate communication capacities of other species. As we have seen, in recent years Chomsky has argued that the language capacity that is uniquely human (being specific to the domain of language) is the ability to form recursive structure. This has led to research to find out whether other animal species can also “handle” recursive patterns either in their communication systems or in other cognitive systems.

In this chapter we enter the field of neuroscience, the study of the structure and workings of the brain. We will focus on the issue of locating brain areas that are activated when people engage in specific activities, especially those that relate to language, which includes producing and perceiving language utterances. We will briefly discuss some methods for the localization of brain functions that were established before modern neuroimaging techniques became available. We discuss instrumental techniques that can be used today to establish which parts of the brain do what. We then review some of the results in modern neurolinguistic work which has revealed very specific brain areas for very specific language functions.

People have always been fascinated by “talking animals.” Dr Dolittle could understand the “languages” of animals, but what if they could use our language? Can they? This chapter reviews various attempts to teach human language, or something close to it, to other animals. Bottom line: They can’t do it. (But we can’t do their “languages” either!)