Another strength of the a posteriori argument is that it isn’t based on a definition, you may argue that a definition is more exact and specific but then I would argue back that definitions are questionable and could be disagreed with. Also arguments based on definition also assume that everyone agrees on the definition, an argument say across languages would then be difficult on definition but if it was based on experience it would be universally accepted.
A posteriori arguments also allow for various conclusions, the problem with this is that you cannot arrive at a certain conclusions only a probability of an argument being correct. The probability of arguments is assessed very subjectively which is another negative point. However if there is a problem with any part of an a posteriori argument, either the premises the logic or the conclusion the argument does not fail it just needs changing, or to be looked upon from a different angle. This could happen with an argument based on something never seen before, something new.
A priori arguments are based on definition. Typically a priori arguments are Analytic, statements which do not require empirical verification because they are true or false by definition. An example is ‘All bachelors are unmarried men’ or ‘1+2=3’. Analytic statements can be either true or false. To get to the conclusion of an a priori argument you use deductive reasoning which is a form of reasoning where the reasoning logically follows the premises to one conclusion.
A priori arguments draw strength from the fact that they are based on agreed upon and fixed definitions and all thee arguments must lead to a single in controversial conclusion. This is a priori arguments strength over a posteriori as there is always one defining conclusion.
It isn’t based on evidence which could be controversial and cannot be distorted by our senses. An example of our sense being distorted is colour-blindness, being deaf, poor eyesight etc. It suffers from none of these problems which could be used to discredit it.
However the definitions an a priori argument is based on may be wrong or not accepted by all. Also if there is a problem or flaw in the argument no matter where it is the whole argument fails completely. Also a priori arguments are based on nothing new and won’t tell us anything real. This is flaw as it cannot be related to life or new experiences, whereas a posteriori arguments can be used to argue about new and real experiences.
So which one is better? Well if you want to come to a single conclusion which is undeniable and conclusive you would use an a priori argument. However at times an a priori argument is not useful at all. What if I was arguing about a football being in my garden? I couldn’t use an a priori argument because it isn’t an argument based on definition which means in life I will be using a posteriori arguments more as they are based on my experiences and my senses. But then using an a posteriori argument it would mean that I have no final conclusion thanks to inductive reasoning. An example of this is if a car goes bye at 130mph (Guess we aren’t in the UK) and no one saw it too well thanks to the dust clouds that blurred our vision. Now what car was it? I say t was a Lotus Elise because it was low down but my friend claims it was a Ferrari because it was red etc. I could do this all day but I am going to conclude that depending on what the circumstance needs both arguments have strong points and weak points.
