LSAT Explanation PT 22, S2, Q1: Braille is a method of producing

LSAT Question Stem

Which one of the following is an assumption on which the conclusion depends? 

Logical Reasoning Question Type

This is a Necessary Assumption question. 

Correct Answer

The correct answer to this question is C. 

LSAT Question Complete Explanation

The passage presents an argument about a new development in technology that allows flat computer screens to replicate Braille patterns using heat. The conclusion of the argument is that anyone who is accustomed to reading Braille can easily adapt to the use of this electronic system. The question type is a Necessary Assumption question, which asks us to identify an assumption on which the conclusion depends.

Let's break down the argument structure:

Premise: Braille is a method of producing text by means of raised dots that can be read by touch.

Premise: A new technology allows flat computer screens to replicate Braille patterns using heat.

Conclusion: Anyone who is accustomed to reading Braille can easily adapt to the use of this electronic system.

An "Evaluate" question for this argument could be: "Can people who are accustomed to reading Braille by touch also read similar patterns on a flat heated surface?"

Now, let's analyze each answer choice:

a) Braille is the only symbol system that can be readily adapted for use with the new thermal screen.

- This answer choice is not a necessary assumption because the argument is focused on the ability of Braille users to adapt to the new technology, not on whether other symbol systems could also be adapted.

b) Only people who currently use Braille as their sole medium for reading text will have the capacity to adapt to the use of the thermal screen.

- This answer choice is not a necessary assumption because the argument is not concerned with who else might be able to use the thermal screen. It only focuses on Braille users' ability to adapt to the new system.

c) People with the tactile ability to discriminate symbols in Braille have an ability to discriminate similar patterns on a flat heated surface.

- This answer choice is the correct assumption because it links the ability to read raised-dot patterns in Braille with the ability to read heated patterns on the flat computer screen. The argument assumes that if someone can read Braille, they can also read the heated patterns.

d) Some symbol systems encode a piece of text by using dots that replicate the shape of letters of the alphabet.

- This answer choice is not a necessary assumption because the argument is only concerned with the new technology's ability to replicate Braille patterns, not with other symbol systems.

e) Eventually it will be possible to train people to read Braille by first training them in the use of the thermal screen.

- This answer choice is not a necessary assumption because the argument focuses on people who already use Braille, not on training new users. Even if the thermal screen is not a good training device, it could still be an acceptable substitute for current Braille users.

In conclusion, the correct answer choice is (c) because it links the ability to read raised-dot patterns in Braille with the ability to read heated patterns on the flat computer screen, which is a necessary assumption for the argument's conclusion to be valid.