nomenal world not only for man but also for animals. for the conditions of its possibility are present also in the latter, these conditions being the a priori forms of sensibility, namely space and time, and the category of the understanding, namely causality (Copleston 267).
For Schopenhauer, understanding is found in animals as well as in human beings. Animals do not possess reason, or the faculty of abstract concepts:
A dog perceives things in space and time, and it can perceive concrete causal relations. But it does not follow that a dog can reflect abstractly about space, time or causality. To put the matter in another way, the statement that the visible world is object for a percipient subject applies as well to a dog as to a man. But it does not follow from this that a dog can kn
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