Another possible foundation has been proposed. This foundation is that there is no such thing as objective truth – that all that is possible is to know that something is subjectively true “for me”. This is the postmodern epistemological foundation.
The problem with this foundation is that it doesn't even hold itself up. We can't come to the conclusion that all truth is subjective if we have no way of being able to establish that something is objectively true – the statement that all truth is subjective is itself a statement that makes objective claims about the nature of truth. This can be written right across the entire output of postmodern philosophy. We are told by postmodern writers (for example, Derrida) that the interpretation of a text depends not upon the author's intent, but upon the reader. This is founded upon the postmodern epistemology, that truth is subjective. But if the same process is applied to the text of the postmodern writer, then it is obvious that his or her writing has no objective force at all.
For people who haven't come across “high postmodernism”, this form of explicit statement about the nature of truth may be something of a surprise. However, you don't have to look very far into our culture to see things like “feminist interpretations of Shakespeare” (with the implicit assumption that Shakespeare's interpretation of Shakespeare doesn't exist, and that this interpretation is at least as good as any other). Also, we now have a culturally instinctive opposition to any statement that sounds like a declaration of absolute truth. For example, I remember a conversation I had once. The person I was talking to said something along the lines of: “I don't smoke, but I think people have the right to do what they choose.” I said: “I think smoking is a stupid, dangerous habit, and the only reason it is allowed to continue is because the government makes so much money from it.” “Well, we're all entitled to our opinions,” was the prickly response – in the sense, presumably, that whilst I might consider smoking to be stupid and dangerous, people were quite at liberty to believe something else if they chose to – whether smoking was stupid and dangerous was a matter of subjective truth. So at the level of normal people, the postmodern idea that truth is entirely subjective is increasingly taking hold.