mun23 wrote:
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.
Need explanation................
Hi,
Let's first identify the elements of the argument:
Conclusion: A newly discovered painting on wooden panel by Michelangelo
must have been completed after 1507 but before 1509
Premise 1: one of its central figures carries a coin that was not minted until 1507
Premise 2: it contains a pigment that Michelangelo is known to have abandoned when a cheaper alternative became available in 1509
Pre-thinking (guessing) an assumption in this argument does not seem easy. So, instead of banging the head on pre-thinking, lets move to the option statements:
(A)No stocks of the abandoned pigment existed after 1509. - This does support the conclusion. If no pigment existed after 1509 and the painting contained this pigment, it strengthens that the painting was completed before 1509. However, does this statement necessarily need to be true for the conclusion to hold? (Remember an assumption has to be true for the conclusion to hold) The answer is No. Even if pigments existed after 1509, it doesn't break down the conclusion. If Michelangelo abandoned these pigments in 1509, then it does not really affect the conclusion whether these pigments existed or not. So, this is not a must be true statement and thus,
Incorrect.(B)Michelangelo did not work on the painting over the course of several years. - I like these kind of negated statements i.e. statements which have "not", "never" kind of words, statements which rather than presenting a possibility, eliminate one possibility. I always deal with these statements by working with their original statements, which these statements negate. So, in the given scenario, I think what would happen if "Michelangelo did work on the painting over the course of several years." - Oh... If this is so, my conclusion would fall apart. How? Because then I cannot say that the painting
must have been completed before 1509 because Michelangelo might have used the pigment before 1509 but since as per given statement, he worked over several years, he might have finished in 1510 or 1511 or even later. Thus, negation of the given statement brings the argument down. Therefore, this is an assumption.
Correct(C)The coin depicted in the painting was known to general public in 1507. - This does not impact the conclusion. Whether it was known in 1507 or not, the conclusion that the painting was made after 1507 does not get impacted.
Incorrect.(D)The wooden panel on which the painting was executed cannot be tested accurately for age. - This is funny. On reading this, you should ask "So what?". This has no relevance to the argument.
Incorrect(E)Michelangelo's painting style did not change between 1507 and 1509. - This is in negative form. So, I think what if "Michelangelo's painting style did change between 1507 and 1509" - I find that even if it changed it does not really harm the conclusion.
Incorrect.Hope this helps
Let me know if any further clarity is needed.
Thanks,
Chiranjeev