I do rely on two premises which can be backed up by observation of the world around us.

Animals are capable of suffering in most of the ways humans can suffer. This includes pain, discomfort, boredom, the distress of losing a loved one, and so forth. Animals can be even diagnosed with many of the same psychological disorders as humans (that’s why they can test antidepressants on rats, for example). Obviously humans are more sensitive to some of these, like boredom. However generally, the same things that cause an emotion in a human will cause the same emotion in an animal. This can all be backed up with scientific evidence. Furthermore if it wasn’t true, animal testing wouldn’t be much use.

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