The whole problem of the relation between parent and subsidiary corporations is one that is still enveloped in the mists of metaphor. Metaphors in law are to be narrowly watched, for starting as devices to liberate thought, they end often by enslaving it. We say at times that the corporate entity will be ignored when the parent corporation operates a business through a subsidiary which is characterized as an 'alias' or a 'dummy.'... Dominion may be so complete, interference so obtrusive, that by the general rules of agency the parent will be a principal and the subsidiary an agent.

Berkey v. Third Avenue Railway, 244 N.Y. 84, 94, 155 N.E. 58, 61 (N.Y. 1926). Sometimes misquoted as referring to "figures of speech" rather than metaphors, or with other minor variations. - Judicial opinions