Few people born after 1960 have heard the Polio; few people born before 1960 can hear the word with feeling terror. Polio is short for Poliomyelitis, an acute, viral infection that inflames the spinal cord and brainstem resulting in paralysis that cripples legs or arms. Even breathing can be paralyzed. Black and white television screens in the 1950s told awful stories of Polio sufferers kept alive by "iron lungs," metal tanks that enclosed all of their body and forced their lungs to inhale and exhale. Iron lungs trapped sufferers permanently.
As the 20th century dawned, polio was the public health horror of the age. First recognized as a distinct illness in 1840, by 1900 Polio epidemics were raging around the world. Hysteria gripped entire nations. Nurses and policemen roamed streets in search of the lame. Black cars patrolled neighborhoods, bringing doctors who searched homes for paralyzed children. Victims were quarantined by the desperate but useless hundreds of thousands.
There were 57,879 cases in 1952 in the US alone - that was when the nation had a fraction of its current population. More terrifying than AIDS or SARS, the cause of Polio was a mystery then. Only one in 100 infections caused obvious symptoms - 99% of those infected were silent carriers.
In 1908, the virus was identified. What followed was a scientific victory for the ages. For four decades trial and error slowly developed a treatment that ended the threat. For 40 years, men like Jonas Salk and Albert Sabin labored, following dead-ends and failures, including a 1954 trial that caused instead of cured polio, until the early 1960s when successful vaccination campaigns began. The experiemental process that sorted two useful vaccines from hundreds of useless treatments has been a triumph - there were just 223 cases of Polio worldwide in 2012.
Trial and error is a practical method of solving problems by testing different solutions until success is achieved, or until one grows tired of trying. Trial and error is itself the result of trial and error. Trial and failure were the words once used to describe teh process of eliminating poor choices through repeated evaluations and tedious reassesments. Imagine 40 years of failed scientific experiments in labs all over the world until the successful Polio vaccine was found - this is trial and error, and it is a very good thing.
Viral diseases are not our only enemies. "The Spirit expressly says that in later times some will depart from the faith by devoting themselves to deceitful spirits and teachings of demons, through the insincerity of liars whose consciences are seared" (I Tim. 4:1-2). Lies, deceitful doctrines and depatures from the faith are as dangerous to souls as microscopic viruses are to our bodies.
Like scientists in a lab, Christians are to "test everything" (I Thess 5:21), "examining the scriptures" (Acts 17:11), and "distinguishing good from evil" (Heb. 5:14) so we can "discern what is pleasing to the Lord" (Eph. 5:10). John explains why. "Do not believe every spirit, but test the spirits to see whether that are from God, for many false prophets have gone out into the world" (I Jn. 4:1).
Imagine what would have happened to the world if determined trial and error had not defeated Polio. Imaging what can happen to us if we do not put the same critical process to work against the evils that seek our souls. Test doctrines; try practices; withhold naive trust. Do not grow tired of trying.