"it is preferable to torture a single person for 50 years than for a sufficient number of people (to be fair, a lot of people) to get dust specks in their eyes.

"it is preferable to torture a single person for 50 years than for a sufficient number of people (to be fair, a lot of people) to get dust specks in their eyes." Only if all living beings are distinct and separate from one another. If however there is a single animating force (i.e. soul) in all living beings, and which experiences everything that is experienced, then things would be preferable the other way around.