But sanity is a construct, and like any construct it can be deconstructed. Actually, the whole worldview called “deconstruction” is an idea that deserves a bit of digression here.

If the basic operating system of a human mind, that is, its sanity, is deconstructed, as sometimes happens when a person’s perceptions are rendered incoherent by drugs or sensory deprivation or mental illness, his interactions with real-world events begin to go beyond his ability to sort and respond. Then he has a “nervous breakdown.”

Real deconstruction of a human’s mindset—that is, the set of programs that a person uses to organize his perceptions of reality— is a phenomenon that can happen, but it is not much like the deconstructionists’ way of analyzing human thinking and interpreting works of literature, art or culture. Deconstruction is at its most abstract, unintelligible heights when a critic is analyzing a work of literature. But it is, in reality, a frivolous activity, an empty word game. 

Deconstructionism as a philosophy is a kind of playing at mental illness. It is correct in asserting that every sane human cognition is part of a “text” and can be deconstructed into its constituent parts, most of which are culturally imprinted and so can be shown to be culturally biased. But complete deconstruction of any “text”—or context, to put it more accurately—would require the deconstructor to deconstruct the constituents and then the constituents of the constituents. What in her whole mindset and her culture's way of socializing her into that mindset has led her to talk and act like this? 

She would have to continue until she had deconstructed her own mind as part of the text being analyzed. In short, she would need to go mad.

Deconstructionists are too cautious to use their method to its logical limit. Mental illness, they well know, is not clever, sophisticated, illuminating, or even merely logical.

But let us set regrets about deconstructionism aside and return to our main line of thought.

The thrust of Bayesianism is this: all of my sensory experiences and memories of experiences would be jumbled, meaningless gibberish without concepts by which I can organize them. Our problem is that these concepts are not built into a supra-real dimension of ideas (rationalism) nor into material reality itself (empiricism). Our minds’ thinking systems are based on concepts that exist only in our minds and only for as long as they are functional, be that for seconds or generations.

All basic concepts are illusions in the sense that they morph constantly into and out of one another. Even trees aren’t all trees; some are giant bamboo, some are bushes grown big, some are former trees in various stages of decay, and some are potential trees (e.g., acorns).

  

                                                        Dingo, a wild dog of Australia.

Dingoes that kill human children are vicious brutes; dingoes being killed by humans are pathetic victims. Nature is beautiful or horrible depending on what point of view it is perceived from. Light is a particle, not a wave; light is a wave, not a particle. Criminals aren’t always criminals; if they wage war on another ethnic group and lose, they are terrorists, the worst of criminals; if they win, they are freedom fighters, the best of heroes.

                                                              Soviet show trials of 1930's 

Justices mete out injustice. Teachers stupefy. Scientists tell lies. Physicians sicken. Not always, of course, not even mostly. But too often for us ever to become smug about our terms. Life is complex and constantly changing. The distinctions we draw to try to justify our versions of reality become subtler and subtler, but they are never subtle enough to be considered complete. Real life keeps cropping up with situations that leave us and our thinking systems stranded in bafflement and ambivalence. Therefore, we learn new ways, we improvise, we evolve.