It was a look so intelligent, yet inexplicable, perverse, sometimes so malicious, but generally accompanied by a wild flow of spirits, that Hester could not help questioning at such moments whether Pearl was a human child.
Heretofore, the mother, while loving her child with the intensity of a sole affection, had schooled herself to hope for little other return than the waywardness of an April breeze, which spends its time in airy sport, and has its gusts of inexplicable passion, and is petulant in its best of moods, and chills oftener than caresses you, when you take it to your bosom; in requital of which misdemeanours it will sometimes, of its own vague purpose, kiss your cheek with a kind of doubtful…
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With that he turned away and once again started inexplicably walking toward the wall.
James Dashner -- The Scorch Trials
For some inexplicable reason, those words popped into Thomas’s mind.