This hypothetical situation implies something I wouldn’t fail to ask first. Are these humans persons or are they “empty”? I don’t see a difference between a {person,experience}-less human and a rat (in this setting, legal and parental implications aside), but maybe you do. Both are able to experience pain and negative emotions. One of them being of a [non-]familiar kind changes nothing to me.

Iow, put yourself into the shoes of that rat or that empty brain and tell:

- which one would you choose to be (if given no other option),

- why,

- and what you expect to sense differently.

Well, is that not basically the vegan argument against suffering, in any form, for any type of animal or sentient being? The vegan would probably posit that they are equal.

Obviously yes, rats don’t deserve tumors.