T4.2: 9 of 9

Good!

Now, bear in mind that there are lots of ways to do any problem. One can say at most two are politicians in a long winded way:

[(A&B)>~C]&([(A&C)>~B]&[(B&C)>~A])

(literally: "if any two are politicians, then the third is not") or much more simply as:

~[(A&B)&C]

(literally: "not all three are politicians"). These are two logically equivalent ways of saying the same thing.


Consider one final subject: You need to be prepared to think deeply about sentences of different form from those we have seen. For example, think about the following example,

If the Yukon is a province then the Canadian administrative laws have changed, in which case the Canadian political situation is in disarray.

To symbolize, first notice that the comma sets off the major break in the sentence. So, the first component of the sentence comes before the comma and is a simple conditional statement: 'Y>L'.

The second component is less obvious. But "in which case" means "if the just mentioned is true". So, in this case it means "if the Canadian administrative laws have changed, then the Canadian political situation is in disarray": 'L>D'.

But what is the main connective which binds these two components? Look closely at the original English to notice it implies that both components are true. So, the connective needs to be '&' and the final symbolization is

(Y>L)&(L>D)

 

Take me to the next tutorial!
Better do some further exercises first...
Back to chapter four, please.