MrStakhanovite wrote:Look at this:
This is an inductive proof for a binomial theorem.
Actually, no it is not. It is merely the binomial theorem itself in the case of the power n+1.
The proof involves quite a few more lines where the proof of the inductive step from n to n+1 would end with the displayed equation or at least its right hand side.
Here is one version:
http://planetmath.org/encyclopedia/Indu ... eorem.html
I would like to add that mathematical induction as used in the proof of the binomial theorem is not the same thing as what is generally called inductive reasoning. It isn't even an instance of the latter.
In fact, mathematical induction is really a form of deductive argument implicitly based on the so called "axiom of induction".
Wiki puts it this way:
Mathematical induction should not be misconstrued as a form of inductive reasoning, which is considered non-rigorous in mathematics (see Problem of induction for more information). In fact, mathematical induction is a form of rigorous deductive reasoning.
I am thinking about some other things mentioned in this thread.
At first blush, I don't see that an argument that is intended to make the conclusion more probable must necessarily have the form of a probabilistic analogue of a deductive argument. I don't think that rational argumentation is exhausted by what that we have formalized --no? I know I have been convinced by arguments that I could never formalize. Sometimes just laying things out in the right way makes things more or less obvious.
It seems relevant to note that while modern probability theory proceeds without any logical problems as essentially a subset of measure theory once the usual axioms are accepted, the very notion of what probability actually means and how at the most fundamental level do probabilistic notions figure into warrant for beliefs is still a philosophical problem with room for disagreement. There are, as most of you know, several approaches to this (I am not happy with letting any one of them dominate to the exclusion the others since no one of them seems sufficient for all purposes).
If we take a subjectivist view on probability, then what would an argument designed to "prove" that something is likely or unlikely amount to when we are faced with anything but an artificially unrealistic toy problem?