Many physicists claim that quantum mechanics may ultimately be able to explain all fundamental phenomena, and that, t...

Naz on September 9, 2015

Conclusion: "we can expect that quantum mechanics will not be the final theory."

Why? "every theory in the history of physics that was thought to be final eventually had to be rejected for failure to explain some new observation."

What is the method of reasoning here? Because something has been consistent in the past, it will continue to be this way forever.

This is the reasoning answer choice (C) takes: "Your sister is a very good chess player but she has never won a chess tournament; therefor she will not win this chess tournament."

So, since historically your sister has never won a chess tournament, she will continue not to.

Hope that clears things up! Please let us know if you have any other questions.

Mia-Partridge on July 2, 2019

I hesitated with C because it states that the sister is a very good chess player, but in the question it doesn't say anything about the quality of the theories. Am I over-thinking it or is there something in the stimulus that should lead me to believe that the theories are also good quality?

Victoria on July 3, 2019

Hi @Mia-Partridge,

Parallel reasoning can be tough because you are comparing abstract methods of reasoning as opposed to directly comparing the stimulus and answer choices themselves. In this way, the fact that the sister is a very good chess player but the stimulus does not discuss the quality of the theories is irrelevant to the question. Rather than taking the statements at face value, we are comparing the underlying methods of reasoning.

The passage is arguing that quantum mechanics will not be the final theory which ultimately explains all fundamental phenomena. The evidence presented to support this is that "every theory in the history of physics that was thought to be final eventually had to be rejected for failure to explain some new observation."

In essence, the passage is arguing: because all other theories that were thought to be final were eventually rejected, quantum mechanics will also be rejected.

Or, as Naz outlined above, because something has been consistent in the past, it will continue to be this way forever.

This reasoning is directly mirrored by answer choice C: because all other times your sister has competed in a chess tournament she has never won, she will also not win this chess tournament.

The fact that the sister is a very good chess player is simply an additional detail meant to distract you from the argument itself.

Hope this is helpful! Please let us know if you have any further questions.