Self-study
Ethicist: Support Every moral action is the keeping of an agreement, and Support keeping an agreement is nothing more than an act of securing mutual benefit. ████████ ████████ ███ ███ █████████ ██ █████████████████ ███ █████ ████████ ██████████ ████ ████ ██ ████████ ██████ ███████ ███ ███ █████ ████████
Method of Reasoning
Two premises form a conditional chain:
Moral action → keeping agreement → securing mutual benefit
Another premise asserts that some “keeping agreement” are NOT moral actions.
The conclusion is a valid inference from claim that “keeping agreement → securing mutual benefit” and “some ‘keeping agreement is NOT a moral action’”:
some “securing mutual benefit” are NOT moral actions
(If we know that ‘A → B → C’ and ‘Some B are NOT A’, then we can conclude ‘Some C are NOT A.’)
20.
The pattern of reasoning in █████ ███ ██ ███ █████████ █████████ ██ ████ ███████ ██ ████ ██ ███ ██████████ █████████
a
All calculators are █████ ██ ██████████ ███ ███ █████████ ███ ███████ ███ █████████ ██████████ ████████ ███ ███ ███████ ███ █████████ █████████ ███ ████████████ ██████████ ████ ███████ ███ █████████ █████████ ███ ███ ██████████
This goes wrong when we get to the “not all” statement. The first two statements look like this:
Calculators → computers → device for automated reasoning
In order to be parallel, we want a premise that asserts some computers are not calculators. But we don’t get that. Instead, we get a premise asserting that some devices for automated reasoning are not calculators.
b
All exercise is ███████████ ███ ███ ██████ ████ ███ ██████████ ███████ ███████ ████████ ███ ███ ██████ ████ ███ ██████████ ███ █████ ██ █████████ ██████████ ████ ████████ ████ ███ ███████ ███████
This goes wrong with the conclusion. The first two statements look like this:
Exercise → beneficial → promote health
Then we’re told that some beneficial things are not forms of exercise. To be parallel, we want the conclusion to assert that some things that promote health are not exercise. But we don’t get that. We get instead the claim that some exercise does not promote health.
c
All metaphors are ████████████ ███ ███ ███ ███████████ ███ ███████████ ████████ ███ █████████ ███ ███████████ ██████████ ████ ███████████ ███ ███ ██████████
This goes wrong with the two conditional premises. We know that all metaphors are comparison and all metaphors are surprising. But these don’t connect to form an “A → B → C” connection.
d
All architecture is ██████ ███ ███ ██████ ██ ████ ████████ ███ ███ ██████ ██ █████████████ ██████████ ████ ███ ██ ███ ███████
This goes wrong with the conclusion. The first two premises look like this:
architecture → design → art
Then we learn that some design is not architecture. In order to be parallel, we want the conclusion to assert that some art is not architecture. But we don’t get that. We get instead the claim that some art is not design.
e
All books are ██████ ███ ███ █████ ███ ██████████ ████████ ███ ███ █████ ███ ██████ ██████████ ████ █████████ ███ ███ ██████
This matches every piece of reasoning. The two premises look like this:
books → texts → documents
Then we learn that some texts are not books. Then the argument reaches the valid conclusion that some documents are not books.