Many scientists also say that it is impossible to prove animals have emotions using standard scientific methods -- repeatable observations that can be manipulated in controlled experiments -- leading them to conclude that such feelings must not exist.

• 许多科学家认为用通常规范的科学方式来证实动物具有情感是不可能的，因为这种反复的观察实验可以在受控的实验中操纵进行，这就使这些科学家得出结论，即动物的这种情感是不存在的。