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LANGER, SUSANNE K (1953)(1967) An Introduction to Symbolic Logic, Dover Publications, New York.
On page 90, under the header:
'Propositional Forms.'
Quote
'Every proposition in a formal context is either true or false. We may not know which it is; but we may rest assured that it is one or the other.
An expression like:
a fm b (90).
Here, a is the fellowman of b or a is in fellowship with b. 'This is true with one set of values and false with another...' (90).
r (Russ) is in fellowship with c (Chucky, my friend since 1989).
r fm c. This is true.
r (Russ) is in fellowship with c (Chucky, the murderous doll).
r fm c. This is false.
The author further explains that:
The expression "a fm b"...is neither true nor false. (90). It is not a proposition at all. 'It is only the empty form of a proposition.' (90). It has to be filled in with particular elements to be an actual proposition. (90).
In my above examples, I filled in with elements. I defined them.
Examples of propositions from my PhD, Wales.
God reveals himself in the Bible
The Father, Son and Holy Spirit are the same God
God is close to all persons
God is beyond his creation
God is in all things
I did not merely present, for example:
a reveals himself in b. By the text standards, that would not be a proposition.
Each question was followed by AS A NC D DS (Agree Strongly, Agree, Not Certain, Disagree, Disagree Strongly).
It is only when all its terms are fixed, it requires a truth value. It then becomes propositional, a proposition. (91).
If no values are assigned to terms, then it is not a proposition. It is an expression. (90).
Langer admits, 'The name is not very fortunate', as in these expressions are called 'propositional forms' even though they are not propositions! (91). This may add to the confusion for those trying to learn symbolic logic.
This type of communication would be at times technical, but appealing to the use of a textbook in the construction of propositions would be reasonable.
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| Ironic that this presentation was hung on the wall at the pub by our table, where we had our post-Bible study, theology talk. But strangely, almost everyone at the table took a photo. |
Matthew 6:9-13
New American Standard Bible (NASB) 9 “Pray, then, in this way: ‘Our Father who is in heaven, Hallowed be Your name. 10 ‘Your kingdom come. Your will be done, On earth as it is in heaven. 11 ‘Give us this day [a]our daily bread. 12 ‘And forgive us our debts, as we also have forgiven our debtors. 13 ‘And do not lead us into temptation, but deliver us from [b]evil. [c][For Yours is the kingdom and the power and the glory forever. Amen.’]
Footnotes:
a Matthew 6:11 Or our bread for tomorrow
b Matthew 6:13 Or the evil one
c Matthew 6:13 This clause not found in early mss
