Philosophical Thought of the Day: Sept. 17th

Actuality and the Laws of Logic
Often in discussions with people, when the laws of logic come up, the conversations seems to run into problems. Especially around the question of conditionals. It seems some people have a problem with unactualized conditionals–in other words conditionals that either have false antecedents & consequents or conditionals that have indeterminate antecedent & consequents.

People seem to be under the impression that a conditional can only be true, if its antecedent & consequent is true. I think the general view can be put as follows,

(A) For any proposition P, if P is a conditional, then P is true if and only if the antecedent P1 and consequent P2 are true. P (P1 & P2) = T

It is ironic that this principle would need a true antecedent and consequent in order to be true — but nevermind that for now. Let’s suppose that is not a problem. Principle A face other problems — it is clearly false.

Example: If my car is out of gasoline & no one puts any more gasoline in the tank, then the car won’t start.

The example just given is true, whether the antecendent & consequent are true or not. In other words, I could be driving my car at a particular time t — in other words the antecedent & consequence are false — and the example is still true. Conditional statements are true independently of their parts for the simple reason that conditionals state what will happen in the event that their parts (antecedent and consequent) are true.

How we know conditionals to be true is another question — an epistemic (knowledge) question. That we know a conditional is true is another matter, and clearly possible.