Critical Reasoning

A newly discovered painting on wooden panel by Michelangelo must have been completed after 1507 but before 1509. It cannot have been painted earlier than 1507 because one of its central figures carries a coin that was not minted until that year. It cannot have been painted after 1509 because it contains a pigment that Michelangelo is known to have abandoned when a cheaper alternative became available in that year.

Which of the following is an assumption on which the argument depends?

A) No stocks of the abandoned pigment existed after 1509.
B) Michelangelo did not work on the painting over the course of several years.
C) The coin depicted in the painting was known to general public in 1507.
D) The wooden panel on which the painting was executed cannot be tested accurately for age.
E) Michelangelo's painting style did not change between 1507 and 1509.

Answer - OA-B

B is right.

A - Whether stocks of pigment existed after 1509 is immaterial. Even if they existed, the argument says that Michaelangelo consciously abandoned its use after 1509.

B - If Michaelangelo worked on the painting from say 1508-1515, then he would have been forced to use the older pigment even after the newer one was available. In that case, the argument would have fallen. Hence, the author assumes that Michaelangelo did not work on the painting over the course of several years.

C - The knowledge of the coin to the general public in 1507 is immaterial. Had this been known before 1507, then a case could have been made.

D - The author is not making this argument on the assumption that the wooden panel of the painting cannot be tested for age. There is no evidence for this intent of the author.

E - The author is making the argument based on the coin and the pigment. Michaelangelo's painting style is irrelevant to the author.