Copyright (C) 2019 Dennis Joe Darland
I’ve spent most of my writing the past 12 years trying to clarify that a S z & b S z does not imply a = b. Here a and b are two ideas standing for the same object. S is the relation between an idea and the object it stands for. If instead of S one uses the P | R | S relation one has a relation between words and objects. P is the relation between a word and the idea of the word. R is the relation between the idea of a word and the idea of the object. “|” is the symbol for Relative Product. This is important because this mistake leads to arguments for opacity & against intensions (mind). Neither really has to do with logic. But that logical mistake causes the appearance that propositional attitudes could involve logical problems. That identicals cannot be substituted for each other. But a and b are not equal even though z equals itself. (i x) (a S x) = (i y) (b S y). So a and b need not be substitutable for each other.
This means I now need only focus on logic. There are not words for every object, or sentences for every fact. There need not be any of either of these. Facts would obey the laws of logic even if there were neither of these. We cannot express every logical truth. But everything we can prove logically is true. I need not be concerned with linguistics or ordinary language. These may be of significance to other areas of philosophy. The laws of logic are necessary. I think laws of physics, psychology, etc are not logical. I think the laws of physics universal although I am unsure whether they should be called necessary. The laws may not be deterministic. Psychological laws are more “geographical” in that they apply to complex configurations of objects. But those configurations also obey laws – it’s just more contingent that those configurations exist. Laws of psychology may partly affect the ideas and words we are capable of using and thus our knowledge of logic – but do not affect the laws (facts) of logic themselves.
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