This thread is inspired by brian0918’s question on the thread entitled “The true nature of religion”, which read:
Those premises involve the concepts “cow” and “animal”, among others. Those concepts were formed by induction/deduction. Show that the inductive reasoning that produced those concepts was done “correctly”, by your standards. In fact, every bit of that statement is the result of concepts produced from inductive reasoning. So how do you know the statement communicates anything?
More generally, the very concept of deductive reasoning, or validity, is itself the result of inductive reasoning - so is it the case that all knowledge hinges on something that could be wrong (and cannot be shown to be right), or is it the case that your standard of truth is not based in reality?
Induction and deduction always complement each other in reasoning, but proper induction is not necessary for the truth of deduction. Induction produces general conclusions from specific instances, but deduction produces knowledge of specific instances from general knowledge. Inductive reasoning is like drawing a regression for given points where deductive reasoning is akin to plotting points when the function is known. Clearly, the regression is just an approximation. The deduction appears to be exact. Brian argues that because one can only form premises for deduction from induction, induction must be epistemologically superior. This is not the case.
Induction leads to the definitions of terms, concepts, and abstractions as Brian adduces. It relies on sense perception. Early man undoubtedly defined objects based on sense perception. The first words probably referred to the senses and were probably colors, sounds, tastes, etc. These terms are defined by sense perception so induction never fails when you use them; if you sense a loud sound, it must be loud. This later results in linking different sense perceptions together. Sensory experiences come in clusters. The same object that is hard and gray, also hurts when it hits someone. This repeated cluster of sensation leads to the word “rock”. The immediate sensations are followed by observed “effects” of the object. Overtime, these effects become equally important to the definition of the term.
The usage of this concept does not depend on one particular sensation. It depends on an imprecise combination of sensations. Sometimes, objects aren’t gray, but they result in every other sensory experience associated with the rock. Also, they produced the same effects as gray objects. Since “rock” is now associated with specific effects, one can call a non-gray object a rock if it satisfies the criteria.
This is why deduction is necessary for induction to have any real meaning. It is deduction and not induction that sorts terms into concepts. When one faces a huge assortment of sensations, one must decide what terms to use to describe it. This is why you need deduction. You need to use the same term to refer to different sensory experiences.
I’ll finish and edit this later if you want.