00:01
As we always do with these problems, we got to start off by defining a few terms and putting them in our own notation.
00:08
We can start off with f of x and define that as is a fish.
00:16
The next thing we need to do is define g of x as has gills.
00:24
And we need to consider our special case of w, which is a whale.
00:32
So, with these three things in consideration, with the statements we have, we have the proposition or the premise that if an animal is a fish, then it must have gills.
00:52
So the way we do it, like always, we start off with a large set of for all x, create a subset of that of fishes for all x.
01:01
If it's a fish, then what must be true? it must have gills.
01:22
Now we can start an oiler diagram for this...