“Language has two lives. In its public role, it is a system of conventions agreed upon by a speech community for the purpose of effective communication. But language also has another, private existence, as a system of knowledge that each speaker has internalized in his or her own mind. If language is to serve as an effective means of communication, then the private systems of knowledge in speakers’ minds must closely correspond with the public system of linguistic conventions. And it is because of this correspondence that the public conventions of language can mirror what goes on in the most fascinating and most elusive object in the entire universe, our mind.

This book set out to show, through the evidence supplied by language, that fundamental aspects of our thought are influenced by the cultural conventions of our society, to a much greater extent than is fashionable to admit today. In the first part, it became clear that the way our language carves up the world into concepts has not just been determined for us by nature, and that what we find “natural” depends largely on the conventions we have been brought up on. That is not to say, of course, that each language can partition the world arbitrarily according to its whim. But within the constraints of what is learnable and sensible for communication, the ways in which even the simplest concepts are delineated can vary to a far greater degree than what plain common sense would ever expect. For, ultimately, what common sense finds natural is what it is familiar with.

In the second part, we saw that the linguistic conventions of our society can affect aspects of our thought that go beyond language. The demonstrable impact of language on thinking is very different from what was touted in the past. In particular, no evidence has come to light that our mother tongue imposes limits on our intellectual horizons and constrains our ability to understand concepts or distinctions used in other languages. The real effects of the mother tongue are rather the habits that develop through the frequent use of certain ways of expression. The concepts we are trained to treat as distinct, the information our mother tongue continuously forces us to specify, the details it requires us to be attentive to, and the repeated associations it imposes on us-all these habits of speech can create habits of mind that affect more than merely the knowledge of language itself. We saw examples from three areas of language: spatial coordinates and their consequences for memory patterns and orientation, grammatical gender and its impact on associations, and the concepts of color, which can increase our sensitivity to certain color distinctions.

According to the dominant view among linguists and cognitive scientists today, the influence of language on thought can be considered significant only if it bears on genuine reasoning-if, for instance, one language can be shown to prevent its speakers from solving a logical problem that is easily solved by speakers of another language. Since no evidence for such constraining influence on logical reasoning has ever been presented, this necessarily means-or so the argument goes-that any remaining effects of language are insignificant and that fundamentally we all think in the same way.

But it is all too easy to exaggerate the importance of logical reasoning in our lives. Such an overestimation may be natural enough for those reared on a diet of analytic philosophy, where thought is practically equated with logic and any other mental processes are considered beneath notice. But this view does not correspond with the rather modest role of logical thinking in our actual experience of life. After all, how many daily decisions do we make on the basis of abstract deductive reasoning, compared with those guided by gut feeling, intuition, emotions, impulse, or practical skills? How often have you spent your day solving logical conundrums, compared with wondering where you left your socks? Or trying to remember where your car is in a multilevel parking lot? How many commercials try to appeal to us through logical syllogisms, compared with those that play on colours, associations, allusions? And finally, how many wars have been fought over disagreements in set theory?

The influence of the mother tongue that has been demonstrated empirically is felt in areas of thought such as memory, perception, and associations or in practical skills such as orientation. And in our actual experience of life, such areas are no less important than the capacity for abstract reasoning, probably far more so.”

THROUGH the LANGUAGE GLASS – Why the World Looks Different in Other Languages (2010), Guy Deutscher (1969). Pages 233 to 235, published by Arrow Books (2011).