Logic 1 Chapter 4 Question

[ringbearer]

In logic 1, chapter 4, a Logical form of a sentence, there is an example of a sentence that is hard to distinguish the different parts. "the little brown haired boy screams very loud'. To make it easier to distinguish the different parts the words ' is a child who' have been inserted, making the sentence 'the little brown haired boy is a child who screams very loud'. The book then states that this form of the sentence means exactly the same as the original version. I do not think this is so. To me the first version implies that the little brown haired boy is sreaming very loudly now. The second version seems to say that the little brown haired boy screams loudly all the time. What do you think about this?

[magistra6]

I think you are right that the two sentences have a subtle difference in meaning. In normal speech, the tense is a very important element. In logic, however, we are, in a way, removing ourselves from actual events in a particular time and just considering the connections between things--what they are or are not. Statements in logical form are therefore in the present tense and use the format A is B. Does this help?
Julia

[Martin Cothran]

In logic 1, chapter 4, a Logical form of a sentence, there is an example of a sentence that is hard to distinguish the different parts. "the little brown haired boy screams very loud'. To make it easier to distinguish the different parts the words ' is a child who' have been inserted, making the sentence 'the little brown haired boy is a child who screams very loud'. The book then states that this form of the sentence means exactly the same as the original version. I do not think this is so. To me the first version implies that the little brown haired boy is sreaming very loudly now. The second version seems to say that the little brown haired boy screams loudly all the time. What do you think about this?

When I say that one statement "means the same thing" as another statement in a book like this, I usually (unless otherwise indicated) mean that the two statements are logically equivalent. Two statements that are logically equivalent can have slightly different shades of meaning. In fact, the exact same statement can be given a different meaning simply by how it is said. What I meant in this case, in other words, is that the two statements are logically equivalent.

Martin