A simpler (but misleading) version of yesterday’s argument says that realists assume (without supporting evidence) that the world is knowable.
In fact, the whole issue of knowability is only relevant while you stick to the idea of truth in spite of the evidence to the contrary.
Not only that, the very idea of truth is a negative reaction: it doesn’t come from finding something “truly true”, but from discovering mistakes in beliefs previously considered reliable (and afterwards trying to remedy the situation by arguing the mistake can’t be that important after all…).
But let me clarify.
Actually, most realists by now have had to admit that the world is not knowable. If the overwhelming evidence against complete reliability of any data-gathering device wasn’t enough, there’s the chaos theories and Heisenberg’s uncertainty principle and all kinds of studies that show that sometimes complexity simply isn’t reducible at all.
But still, realists keep assuming that the world does have some truth that we could get to know, if only we had the means. That the ultimate form of reality can fit into our heads, except that we just won’t ever get to this point in the game.
If we do not assume reality to possess this elusive property of truth, if we adopt the ‘there is no truth’ slogan, we can make things easier.
To illustrate: if i have some ideas, some of which end up going bust, i can just elect an adequate measure for usefulness of ideas (i usually call it relevance, but suit yourself) and go about trying to find ways to measure it. For example by repeating some given experience. Or by seeking new experiences and trying to witness different things.
I do not have to worry about metaphysics and wonder where do knowledge comes from.
On the other hand, if i draw a divide between truth and falseness (not truth and false, mind), i have just devised a category that is impossible to measure. Truth is impossible to measure.
Obviousness is measurable. Very simple issues are measurable. Truth itself is not.
No matter how precise the measuring instrument, or how many different people you put to the measure, or how many schemes You devise to enhance the reliability of the measure, you are not measuring truth itself. You are also not enhancing the truth-content of the measure. You are making it more reliable, but you can never know that the number you achieve after the measuring has anything to do with “reality”.
Although the assumption of truth is fairly reasonable, when you are for example dealing with day-to-day issues, when you can easily swap “truth” for “sincerity” or “obvious”, to say this proves the importance of the idea of truth is like saying that Santa Claus exists because we teach it to our children.
I do not mean, either, that only scientists should recognize the non-existence of truth. Almost all the Relationships Arguments would be cut short if people simply accepted that they are not dealing with truth but instead negotiating their own behaviours.
After discovering that there are ideas that we have that simply are wrong, we come up with the assumption of truth. After discovering there is no reliable measure for truth, we should move on and devise better criteria for our ideas. This is not so difficult.
This nonsense that if we abandon the idea of “Truth” we will also abandon all possible reference to an external world is simply wrong. It is overly simplistic.
I can still say “that is simply in obvious discordance with all my previous experience” to the foolishness i hear. Which, by the way, i usually abbreviate to “this is simply not truth”.
But there is no external reality that can be used as an absolute reference to knowledge. Simply because all of the external reality has to go through our unreliable senses and brains. There are no shortcuts in this path. At least none that i know of, if you find one please let me know.
Truth is not security of knowledge. It is just illusion of security.