The excerpt represents the core issue or deciding factor on which you must meditate, and is drawn from Expression of Emotion in Man and Animals by Charles Darwin:|
a thing as pulling on a boot, frowns if he finds it too tight.
Some persons are such habitual frowners, that the mere effort
of speaking almost always causes their brows to contract.
 `Mecanisme de la Physionomie Humaine,' Album, Legende iii.
 `Mimik und Physiognomik,' s. 46.
Men of all races frown when they are in any way perplexed in thought,
as I infer from the answers which I have received to my queries; but I framed
them badly, confounding absorbed meditation with perplexed reflection.
Nevertheless, it is clear that the Australians, Malays, Hindoos, and Kafirs
of South Africa frown, when they are puzzled. Dobritzhoffer remarks
that the Guaranies of South America on like occasions knit their brows.
Expression of Emotion in Man and Animals