‘All men by nature desire to know,’ wrote Aristotle. But in this post-truth era where fake news abounds, emotions trump facts, and the truth has allegedly ceased to matter, we might wonder, says Dr Michael Hannon, how important is knowledge in daily life.

Even philosophers have criticised the value of knowledge. In recent years, scholars have claimed that we can fully explain rational behavior without appealing to knowledge, that knowledge is an incoherent notion we are better off without, and that it is a downright myth – we never had knowledge and we never will.

How accurate are these allegations? To better understand the nature and value of knowledge, I believe we should start by investigating why humans think and speak of knowing. Put another way, we should investigate the social role of the concept of knowledge. This is precisely the aim of my new book, forthcoming with Oxford University Press, titled What’s the Point of Knowledge?

Let’s start with some linguistic data. ‘Know’ is one of the 10 most commonly used verbs in English, outpaced only by utterly basic verbs like ‘be,’ ‘have,’ ‘do,’ ‘go,’ and ‘say.’ It is also the first cognitive verb that children learn and the most frequently used term in epistemic appraisal. For example, it is far more common for us to speak of ‘knowledge’ than it is for us to speak of ‘justification’, ‘reliability’, ‘understanding’, ‘thinking’, and an array of other epistemological notions.

Perhaps most strikingly, the word ‘know’ seems to find a comfortable meaning equivalent in every human language. This is remarkable because empirical evidence indicates that almost every English word does not have an equivalent in many, perhaps most, other languages. Even words that refer to common emotional states like ‘sad’ and ‘angry,’ as well as words for seemingly universal mental states like ‘believe’ and ‘remember,’ are language and culture specific. In contrast, linguists have isolated ‘know’ as one of a very small number of words that are allegedly culturally universal.

What does this suggest? It seems to indicate that knowledge is deeply important to human life. If all human societies find it necessary to speak of ‘knowledge’, then perhaps it answers to human interests so basic and universal that we cannot imagine anything like our contemporary, cooperative life without it.

Consider the following hypothesis: humans speak of ‘knowing’ to identify reliable informants. While this idea is quite simple, I believe it has wide-reaching implications. In particular, identifying people as ‘knowers’ helps us collaborate with others to achieve important goals such as sharing information and signalling when to appropriately end inquiry.

By identifying people as ‘knowers’, we are telling members of our community that a particular informant has information that is good enough for us to believe and act on. That’s the point of ‘knowledge’. If this idea is correct, it will reveal the vital social role of knowledge in human survival, cooperation, and flourishing.

Recent work in evolutionary theory supports this idea. In The Evolved Apprentice, Kim Sterelny emphasises our reliance on others to learn valuable skills for survival. One of the most distinctive features of human life, he claims, “is our dependence on intricate networks of cooperation and the division of labor.”

Our competence is a collective achievement that depends on myriads of ordinary individuals who gather and share the informational resources on which human life depends. What’s more, this type of cooperation and information exchange is believed to have ushered along our sharp divergence from our great ape relatives. It is what led to our distinctive intelligence and cognitive power.

But in spite of this cooperation, we all live in epistemically hostile environments populated by liars, bullshitters, conspiracy theorists, untrustworthy websites, Twitter bots, biased thinkers, and many other information sources of dubious merit. In fact, undermining the social value of knowledge has likely been a deliberate political tactic designed to spur discontent and promote the interests of certain political platforms.

If this new research is on track, then we must conclude that knowledge plays a vital role in our social life. In future work, I plan to explore ways in which theorising about politics might benefit from the conceptual tools of epistemology. By fusing epistemology with political philosophy, I hope to generate new ideas that can help to make progress in the current crisis over truth and knowledge in our democratic world.

Dr Michael Hannon is deputy director of the Institute of Philosophy at the School of Advanced Study, University of London. He has a book under contract with Oxford University Press, entitled ‘What’s the Point of Knowledge?’ and he is currently working on one about the role of facts and knowledge in democratic politics, tentatively titled ‘Truth, Reason, and Political Knowledge’. Dr Hannon is also a visiting research fellow at VU Amsterdam as part of a project on ‘Knowledgeable Democracy: A Social-Epistemological Inquiry.’