Question

Imagine that you buy a new computer system with independent components including a new desktop computer (with a CPU and a graphics card), new software, and a new monitor. You want to play games on the new system, but it runs games very slowly. You assume that the keyboard and mouse are not creating the problem; so, to figure out what is making the system run so slowly, you experiment with combinations of your old equipment with the new equipment. Here are your experiments and results:

Experiment 1: New computer, new software, and new monitor — and it runs slowly.
Experiment 2: New computer, new software, and old monitor — and it runs slowly.
Experiment 3: New computer, old software, and new monitor — and it runs fast.
Experiment 4: New computer, old software, and old monitor — and it runs fast.
Experiment 5: Old computer, new software, and new monitor — and it runs fast.
Experiment 6: Old computer, new software, and old monitor — and it slowly.
Experiment 7: Old computer, old software, and new monitor — and it runs fast.
Experiment 8: Old computer, old software, and old monitor — and it runs fast.

Based on this data, which experiment shows that the conjunction of the new software and the old monitor is NOT SUFFICIENT for the system to run slowly?

• A. Experiment 1
• B. Experiment 2
• C. Experiment 3
• D. Experiment 4
• E. Experiment 5
• F. Experiment 6
• G. Experiment 7
• H. Experiment 8
• I. None of these experiments

Answer 1

Experiment 2 is the suitable solution to show the conjunction of the new computer and the new software is NOT SUFFICIENT for the system to run slowly

Experiment 2 used both the new computer and also the new software (X is present), and the system ran fast rather than slowly (Yis absent), so Experiment 2 refutes the claim that, whenever a system includes both the new computer and the new software (X is present), that system runs slowly (Y is present). Thus, Experiment 2 shows that the conjunction of the new computer and the new software fails the negative sufficient condition test, so this conjunction is not sufficient for running slowly.

No other experiment had the conjunction of the new computer and the new software without running slowly, because the only other experiment with the conjunction of the new computer and the new software was Experiment 1, and the system ran slowly in Experiment 1. Thus, no other experiment shows that the conjunction of the new computer and the new software is not sufficient for running slowly.