بِأَنْ يَجْعَلَ الرَّجُلَ الشُّجَاعَ فَرْدًا مِنْ أَفْرَادِ الْأَسَدِ
By treating the brave man as one member of the class of lions.
This does not assert a biological transformation. It is a rhetorical claim of membership: the man's courage is portrayed as so remarkable that he is counted among lions rather than merely compared with them.
The difference between asserted and actual membership is essential. The person remains human, while the utterance constructs an emphatic conceptual identity. In the intellectual theory, the force of the figure lies more in the mind's new predication than in a simple replacement of dictionary meanings.