Systematic Tool Use and Language Are Key to Human Uniqueness

I said previously that human self-conscious awareness arose as a consequence of two other unique human attributes, our capacity for language and our ability to continually transform the world by designing and using technology. In fact, there is another vital factor in what makes humans unique, our brains, which are not just bigger than those of other primates, but as I’ll seek to show later in this post, radically different in structure and function, both at molecular and cellular levels and in terms of gross structure. In fact, these three capacities are all interconnected in terms of their evolution.

But what about my claim that human language and the way we use technologies to transform the world around us are unique to our species? In fact, some would dispute this uniqueness. For instance, such people might point to the fact that other species communicate through various sounds and gestures, or to evidence that not only other primates but also other types of animals, such as crows, develop and use tools. I believe that such arguments are ignoring some key qualitative differences between human beings and other species. To understand why it is worth looking in more detail at how humans first evolved from apes and how this gave rise to the unique characteristics of our species.

The first person to identify the correct sequence of human evolution was Friedrich Engels, which may come as a surprise to those who only know him as a political activist and thinker. In an essay he wrote in 1876, Engels proposed that human beings first began to diverge significantly from other primates when our ancestors started walking on two legs. This freed the hands for using and designing tools, and as a consequence proto-humans began using tools in a systematic way to transform the world around them. Importantly, such tool design and use were carried out with other proto-humans in a socially cooperative manner. And because of the need to communicate with others about how to carry out such innovative actions, our ancestors also began to develop language. Subsequently, the development of both systematic tool design and use, and language, led to a dramatic growth of the brain.

Accumulated fossil and DNA evidence has subsequently confirmed such a sequence of events, although in contrast to the linear progression that Engels envisaged, human evolution was more a case of multiple proto-human species with different characteristic features co-existing, and quite a number of blind evolutionary alleys along the path to Homo Sapiens. As well as the fact that tool use is systematic to the way that humans interact with the world, in contrast to the more accidental and occasional use of tools by other species, another key distinguishing feature of human beings is the way we are continually in a process of inventing new types of tools and technologies. And while this was a relatively slow process early in our prehistory, in modern times it has accelerated to the point that we now take for granted the way that revolutionary new technologies develop with each successive generation.

If such is the case for tool use, what about language? Here, one mistake to make would be to assume that human language is just a means of communication. As a consequence, it might be argued that because other species communicate with each other, there is nothing unique about this human ability. But this overlooks a highly distinctive feature of human language, namely that it is an interconnected system of abstract symbols, linked together by grammar in such a way that it can convey abstract meaning. It is for this reason that I believe only human beings have the ability to use language to convey a sense of the past, present, and future, you versus me, location in space, and even more abstract concepts.

Underpinning the two unique human attributes of systematic tool use and language is a brain that has specifically evolved to give us the capacity to handle these attributes in a meaningful way. And showing how such a capacity is a unique feature of human biology, attempts to teach sign language to our closest primate cousins, chimpanzees and gorillas, have demonstrated that while such species can learn to associate words with objects and even emotions, other primates lack our grammatical capacity, and as a consequence the ability that human beings have to represent the world through abstract symbols in a complex and rational fashion.

If systematic use and development of technology and language capacity are unique features of the human species, what about the way our brain works compared to other species? Here we face a problem for while it is possible to objectively study tool use and language in humans and compare this to the abilities of other species, what goes on inside an individual brain of a human or other species, particularly at the subjective level, is far harder to assess. But I believe that we can gain an objective understanding of what makes human consciousness unique, both through psychological analysis and by studying the ways in which the human brain differs from those of other species in both structure and function.

I will be exploring what we have learned so far in this quest later in this blog. But what we also need is a firm conceptual foundation for such analysis, and in particular, that requires a better understanding of the links between human thought and language, and how language has transformed human thought in a way that makes it qualitatively different from the thoughts of other species, which I will look at in the next post in this blog.