An empty Abstraction, a mere ideality, of no practical use. Every noun is an abstraction, but the narrower genera may be raised to higher ones, till the common thread is so fine that hardly anything is left. These high abstractions, from which everything but one common cord is taken, are called empty abstractions.
For example, man is a genus, but may be raised to the genus animal, thence to organised being, thence to created being, thence to matter in the abstract, and so on, till everything but one is emptied out.
Source: Dictionary of Phrase and Fable, E. Cobham Brewer, 1894
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