It is notorious how much domestic animals vary in their mental qualities.

众所周知，家养动物的心理素质差异很大。

This claim to a soul or special mental quality, even to this day, often has the implicit assumption that our consciousness is a reflection of something higher.

即使在今天，这种灵魂或特殊精神品质的说法也常常隐含着这样的假设：我们的意识是对某种更高层次事物的反映。

That the mental qualities of animals of the same kind, born in a state of nature, vary much, could be shown by many facts.

许多事实可以证明， 在自然状态下出生的同类动物的心理素质差异很大。

We shall thus be enabled to see the part which habit and the selection of so-called spontaneous variations have played in modifying the mental qualities of our domestic animals.

因此，我们将能够看到习惯和所谓的自发变异的选择在改变我们家畜的心理素质方面所起的作用。

We have no indications of the mental qualities of Su Tungpo's mother's family, but a fortuitous combination of the blood of the Sus and the Chengs somehow produced the literary genius.

对于苏东坡外婆家的才智如何，我们尚无明证，但是苏程两家血统的偶然混合，不知在何种情形之下，竟产生了文学天才。