A species in which mutations frequently occur will develop new evolutionary adaptations in each generation. Since spe...

Mario on March 24, 2016

Answer A To Confirm

Answer A is flawed as well by assuming a necessary condition will bring about the sufficient correct? It's just not flawed in the same pattern as the stimulus or the correct answer because it does not conclude the existence of a sufficient condition of a premise to conclude the sufficient of another, when it in fact only provides us with a necessary condition

1 Reply

Mehran on March 27, 2016

@MARIO no (A) is a valid argument. The argument would be diagrammed as follows:

P: "In a stone wall that is properly built, every stone supports another stone."

PB ==> ESSAS
not ESSAS ==> not PB

P: "Since a wall's being sturdy depends upon its being properly built..."

S ==> PB
not PB ==> not S

C: "...only walls that are composed entirely of stones supporting other stones are sturdy."

S ==> ESSAS
not ESSAS ==> not S

This is a proper transitive inference, i.e. S ==> PB ==> ESSAS.

Hope that helps! Please let us know if you have any other questions.