Thanks for your fascinating questions. I’d like to address each of them, but I’m already over my limit for posting this week. I’ll limit this post to just one issue.
I don’t see any problem with the human capacity for understanding the notion of truth. Indeed, you will have noticed that I reframed your ‘concept of truth’ into ‘notion of truth’. A concept is more fixed than a notion. The concept of time is still a human construction, but it’s one that is relatively stable. We can say, pejoratively, that ‘so-and-so’s notion of time is strange’, and in doing so, we are alerted to the individual and subjective tendency in the concept of notion (ha ha). As my truth can be so different from yours, I relegate the term to a notion.
Winch and Gingell (2008) argue that the social construction of various truths “may prove to be unviable and the ‘knowledge’ held by the community may turn out to be nothing more than communally held falsehoods” (p. 218). They use this as a premise to decide that this position is extreme. However, it should be noted that there have been whole systems of belief that are founded on “communally held falsehoods” such as the geocentric planetary system that were inculcated into community members as truth. Winch and Gingell (2008) separate subjective truth (which includes Popperian unrefuted hypotheses) from objective truth, which consists of knowledge that is refined over time by communities. This distinction between the individual sense of truth and knowledge shared is important.
What is more interesting than a discussion of truth may be the understanding that what is ‘real’ may be unknowable (Winch & Gingell). Moses and Knutsen (2012) present Kant’s 12 “pure concepts of understanding” (p. 172) as the primary interface between humans and reality, but they admit, in line with Winch and Gingell, that “it is beyond our capacity to observe” the Real World (p. 173).
Having said that, I do believe that humans have cognitive biases (Ruth, 2015) that substantively affect our interaction with the Real World and with the constructed truth statements of others. Uncovering them is akin to uncovering our assumptions about research.
Moses, J. W., & Knutsen, T. L. (2012). Ways of knowing: Competing methodologies in social and political research (2nd ed.). Basingstoke: Palgrave Macmillan.
Ruth, M. (2015). Cognitive bias. In Salem Press Encyclopedia of Health (Research Starters). Salem Press. Retrieved on Jan 13, 2016 from: http://eds.b.ebscohost.com.ezproxy.liv.ac.uk/eds/detail/detail?sid=c8d44c5b-1ee3-4d29-a2c7-a6d26b11af26%40sessionmgr113&vid=1&hid=104&bdata=JnNpdGU9ZWRzLWxpdmUmc2NvcGU9c2l0ZQ%3d%3d#AN=100259337&db=ers
Winch, C., & Gingell, J. (2008). Philosophy of education: The key concepts. The effects of brief mindfulness intervention on acute pain experience: An examination of individual difference (2nd ed., Vol. 1). Abingdon: Routledge. http://doi.org/10.1017/CBO9781107415324.004