In today’s press there are a number of clear examples of the fundamental and critical difference between explaining and predicting. The type and quality of knowledge required for each are substantively different.CBS leads this hour’s Google news offering with the following: “How Obama became the man to beat.”But, wait a minute. If CBS understands how Obama became the man to beat, why did they not predict his success two months or even two weeks ago? Why is it that everyone can tell us now why and how Clinton has fallen, but these same pundits were predicting that she would be the Democrat’s nominee. What happened?Nothing happened. The problem is knowledge. There is a world of difference between explaining something that has already happened and predicting it beforehand with regard to the quality of knowledge that is required. The day after some newsworthy event, conversation revolves around the question, “why did it happen?” Explanations abound. There is nothing easier in the world than explaining something that has already happened. If 100 people do it, there are 100 different explanations. One of them may even be right!The difficulty confusion about the cause/effect relationship that is described. Science (as we commonly understand it) is built on the premise that there is a way that things are and that what happens around us is the result of causes giving rise to necessary effects.In prediction, a theory states that if a given set of conditions are present, a given outcome will take place in the future. Explanation says that a given outcome took place because a given set of conditions were present in that past.The cognitive process is different in these two cases.In the first some theory or hypothesis is devised and then tested. This testing is critical. In order for a hypothesis to have scientific meaning, it must be testable. It does not have to have been tested, but a test must be possible. Einstein’s theories were not tested until many years after he wrote them, but they were written in a testable form.In the second case (explanation) a pool of potential causes is imagined and what the explainer considers the mostly likely antecedent is selected and designated the cause. Maybe it is maybe it isn’t, but there has been no test. The hypothesis is not put to the test, nor can it be since it has already happened. Statements arising this way may be interesting; they may even be true. But they lack scientific rigor.As a consumer of information, one might consider the type of assertion that a writer is making. Is he or she predicting something or making statements about what is likely to happen in the future? Or is the person inventing an explanation for something that has already happened. There is a world of difference between the two.