In no case may we interpret ...

In no case may we interpret an action [of an animal] as the outcome of the exercise of a higher psychical faculty, if it can be interpreted as the outcome of the exercise of one which stands lower in the psychological scale.
In no case may we interpret an action [of an animal] as the outcome of the exercise of a higher psychical faculty, if it can be interpreted as the outcome of the exercise of one which stands lower in the psychological scale.
 C. Lloyd Morgan

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