Art of Deduction, the Requirement of the Scientific Method, and the Possibilities of Abductive and Holmesian Reasoning.

     Deduction.  In the realm of logic, deductive reasoning links premises with conclusions. In detective work, evidence links people with crimes.
     There is a saying: "If it bleeds, it leads."  In reality, this is often the case. Still, it would be good to question your own judgement.
     Deductive logic is only as good as your premises. For example, if your premise is all people who know that Sassafras Muppet jig is as password are members of the Order of banjos, then if Joebob knows this, he is a member of the Order of banjos.  That premise could be wrong, but if it is evident that Joebob knows, it would be generally considered that he is of the order of banjos, even if he somehow found out the password without being a member. Still, the argument would be valid till disproven by evidence.
    Many premises can not be inverted. For example, while it is correct to say "every man is a being", it is not correct to say "every being is a man." Also, many premises aren't entirely true and therefore false. Thus, it would be wise to question a premise.
   Yes, I will be talking on other subjects such as forensics, cryptography, martial arts, and psychology, but wouldn't you agree that finding out what happened is sleuthing?

   The scientific method is observation, hypothesization, prediction, testing, analysis, and replication. The requirement for  using the scientific method is empirical(observable), measurable evidence.  I will be refering back to these steps when I speak of forensics. In profiling, the steps are respectively observation of all known data, analysis, and prediction.

"From a drop of water, a logician could infer the possibility of Niagara Falls or the Atlantic Ocean without having heard of either."  Unfortunately, there are so many possibilities. This is abductive reasoning or observation and hypothesis.
Holmesian deduction is either inferring from principles based on careful observation or else inferring to the best explanation. Quite often the detective used several principles to arrive at a conclusion.


When you have eliminated the impossible, whatever remains, however improbable, must be the truth.
 -Sherlock Holmes