Christopher asked:
Can’t you have knowledge of the future? For example, I know that I am going to work at 8am tomorrow. In this way isn’t truth ‘made’ rather than existing a priori? Therefore, truth would be mutable and have a subjective quality to it. Or can knowledge not be attained through inductive reasoning? I’m thinking of knowledge as justified true belief. I also realize that there is the possibility that I will not go to work tomorrow at 8am, but isn’t there always a chance that you’re wrong.
Answer by Martin Jenkins
To state on Sunday that ‘I am going to work at 08:00 tomorrow’ is either true or false.
If at 08:00 on Monday I am at work then the earlier statement made on Sunday would be true. If it is true on Monday that I am at work and that what was said on Sunday was also true then it cannot be true that I would not be a work on Monday at 08:00. Therefore, out of necessity, I could not not have gone to work on Monday at 08:00. Necessarily, I will be at work at 08:00 on Monday. A version of determinism (fatalism) follows.
This could be denied by saying, ‘Well, neither ‘I will go to work nor ‘I will not go to work’ are true.’ As this denies the principle of bivalence – the ‘truth’ of ‘Either true or false’ regarding the statement – it becomes nonsensical. Nothing and everything can be known or predicted. Anything goes according to chance and caprice. Indeterminism follows and no statement could be made concerning work at 08:00 on Monday.
So, we sit on the horns of a dilemma. Either we adopt the scenario of Necessity – that I necessarily will be at work at 08:00 on Monday and everything that occurs, occurs by necessity: determinism or; adopt the scenario that nothing can be known or predicted and anything could happen – a reliance upon chance and contingency: indeterminism.
That the statement concerning 08:00 on Monday was made on the prior Sunday entails that the actuality of Monday at 08:00 is/was not yet known. There is a temporal gap between the time of the statement and the truth of what it states. It is not therefore, subject to the judgements of either true or false. For the statement that ‘I am going to work’ includes the word ‘going’: implying an intention, an action, not a conclusion affording an immediate a priori judgement, true or false. Its truth or falsity remains ‘up for grabs’.
Such a proposition as ‘I am going to work at 08:00 tomorrow’ is a future proposition. Future propositions are neither true or false at the time of utterance, they may at most be supported by inductive probability but they can only be verified at the time or subsequently. Only then do they become knowledge. Prior to this, they are neither true or false.
If I am at work 08:00 Monday, then I can conclude that necessarily, I am at work. It is true that I am at work and false that I am not at work. However, I cannot conclude that therefore of necessity, I had to be at work at 08:00 and yesterday’s statement was true; for at the time of Sunday’s statement, it was logically possible that I would not be at work at 08:00 on Monday morning.
I hope this is useful Christopher.
Ask a Philosopher 
