How do you combine Most and All conditional statement in logical reasoning?

Question

I'm struggling with combining these statements in logical reasoning. Are they combined in the same way All statements are combined?

Answer 1

There are two ways to combine ALL and MOST statements. The first method is similar to combining ALL and SOME statements or MOST and MOST statements. To do this, we must make sure the sufficient conditions of the two statements are identical. When this occurs, we can infer a SOME statement. For example:

Most Elephants are large. Most Elephants are grey.

Elephants M---> Large

Elephants M---> Grey

Since the term elephant is on the left-hand side of both conditional statements, we can infer a SOME statement between the two necessary conditions: SOME things that are Large are Grey.

The second way to combine ALL and MOST statements is more difficult. To do this, the necessary condition of the MOST statement must be identical to the sufficient condition of the ALL statement, allowing us to infer a MOST statement. Another way to put this is that the MOST statement must appear first in the logical chain. For example:

Most Lawyers are intelligent. All intelligent people enjoy learning.

Lawyers M---> Intelligent

Intelligent ----> Enjoy Learning

Since the term Intelligent is shared between the necessary condition of the MOST statement and the sufficient condition of the ALL statement, we can infer a MOST statement. We can combine the two statements to get

Lawyers M---> Intelligent ----> Enjoy Learning

Which can be shortened to Lawyers M---> Enjoy Learning, or “Most lawyers enjoy learning”

It is important to note that the first method of combining MOST and ALL allows us to infer a SOME statement while the second method allows us to infer a MOST statement.