In his book, The Discoverers, Daniel Boorstin wrote, "The greatest obstacle to discovering the shape of the earth, the continents and the ocean was not ignorance but the illusion of knowledge." Many of the great discoveries about the world we live in would have come sooner had not those who had erroneous theories been so reluctant to take a fresh look at the situation. And in our own lives as well, the growth of our knowledge is hindered by the "illusion of knowledge," the conviction that we know something when, in fact, what we know is inaccurate. Will Rogers seems to have understood this when he said, "I'm not worried about what folks don't know - it's just that so much of what they do know ain't so!"
There is nothing that will more surely block out new knowledge than the closed-mindedness of the man who thinks he already has all the information he needs. It's hard to impart new facts to a person if he is immutably satisfied that his present knowledge is all-sufficient. Since omniscient people make poor students, the know-it-all's attitude will keep him from ever really knowing much of anything. In regard to spiritual matters, Paul wrote, "And if anyone thinks that he knows anything, he knows nothing yet as he ought to know" (1 Cor. 8:2). And he described certain ones this way: "Professing to be wise, they became fools" (Rom. 1:22). The wiser we think we are, the more foolish we truly are, and our foolishness is probably obvious to everybody but us!
In the wisdom literature of the Old Testament, one of the main differences between wisdom and folly is that the wise person is teachable, while the fool is not. No matter how much he thinks he knows, the wise individual has the humility to be corrected, to learn, and to improve the accuracy of his understanding. The fool, on the other hand, never advances beyond the limitations of his present thinking because he thinks he's right about everything already. "The way of a fool is right in his own eyes, but he who heeds counsel is wise" (Prov. 12:15). "A fool has no delight in understanding, but in expressing his own heart" (Prov. 18:2).
These truths in the Old Testament are consistent with what is taught in the New about the need for us to be more ready to hear than to speak: "So then, my beloved brethren, let every man be swift to hear, slow to speak, etc." (Jas. 1:19). We learn so much less than we could learn because our mouths are in motion when our ears should be operating. Too much of the time, our communication apparatus is set to "transmit" when it should be set to "receive."
What is needed in life generally, and especially in spiritual matters, is the humility to recognize how little any of us do know. We need to guard against the "illusion" of knowledge - the false impression that we know much when really we know only little. We need to be suspicious of any of our ideas that may be mistaken. If not, we will never correct those which are.
There is, of course, a problem in the opposite direction. If our idea of open-mindedness requires us to put a question mark over everything we know, then we've simply exchanged one kind of foolishness for another. Unfortunately, thinkers in our age often seem to do exactly this. In a day when respectable philosophers can say they're not "sure" even of their own existence, the worst sin a person can commit on any subject is to be "dogmatic" about it. The words "truth" and "knowledge" have acquired condescending little quotation marks, and we're told that we can believe anything we want...as long as we're not sure of any it.
Certainly, it would be dangerous to give in to this skepticism about knowledge in general. But it would be equally dangerous never to re-evaluate any notion once we have accepted it as true. There are times to honestly reconsider what we have believed and there are other times to stand firm for what is assuredly true. Common sense can usually tell the difference.
Paul wrote, "Let no one deceive himself. If anyone among you seems to be wise in this age, let him become a fool that he may become wise" (1 Cor. 3:18). Real knowledge and wisdom are always accompanied by humility. It is the person who is willing to learn who will learn. Admitting that one is yet uninformed about many things is a painful, pride-destroying step, but it is one that must be taken around nearly every bend on the road to true wisdom.