Logic is considered to be the only means to derive truth. The argument goes: “truth requires a logical argument” or “any argument against logical necessity for truth requires logic itself, so logic can never be dismissed“. This is true if we define truth to be that which is determined by logic. However, this is a circular argument. It isn’t necessarily true.
Why do we assume logic to be necessity for truth in the first place, before we defended this position? We experienced that logic was consistent. Therefore, logic is not a fundamental phenomena. In fact, it is derived from our experience of it being a reliable tool to predict propositions given premises. You can make a logical case that Socrates is a mortal. However, if you experience that he is immortal, then the logic is wrong despite it being a sound deduction. You might then say, “therefore, men are not necessarily mortal“. However, this is just moving the goal post to make logic fit the experience. Logic is an attempt to render truths. It is not the truth.
At first, this argument seems to contradict this claim. However, we are using logic as a tool to communicate an idea that logic is second to experience. This is not not saying the experience is fundamental knowledge either, rather it is to disprove that logic is necessarily fundamental.
Can you derive truths from logic? You can, but you don’t know they’re true. You only know they’re true to the degree that logic is experienced as being reliable. As we are unable to invoke experiential knowledge, we must formulate knowledge to the best of our ability. Thus, the existence of logic does not prove itself as proof, but rather proves that it is not itself proof necessarily.