Determinism can also take another form. Instead of 'physical determinism', in which the nature of matter and causality is considered, there is 'logical determinism'. This approach attempts to prove the deterministic nature of the world through logical truths alone. A logical argument for determinism follows:
Consider tomorrow's weather. Either it will rain or it will not rain. One of these must come about. So, it is either true that it will rain, or true that it will not rain. But if one is true, then it must come about - otherwise it would not be true. So there exists a true statement about tomorrow's weather, implying it is fixed and determined.
Logical Determinism is an approach that seems wrong, but it's not easy to see why. My opinion is that there has been a logical error - the argument mistakenly assumes that 'either it will rain or not rain' means the same as 'either "it will rain" is true, or "it will not rain" is true'. In fact:
A or B = True
Does not mean
A = True OR B = True
The Logical Determinist's conclusion does not follow from the premises. Even if the world were indeterministic, it would be possible for us to make statements that happened to accurately predict future events by simple coincidence. The truth value of a specific prediction (For example, A = True) is not set until the event has occured.