The different temperaments among men have from ancient times, with great unanimity, been classified as four...
A predominant energy and activity given to the nervous system induces the sanguine temperament. In the nervous system provision is made for animal sensibility and motion; and where this is preeminently vigorous, the individual is prompt to respond to every excitement. In this is the peculiarity of the sanguine, or, as sometimes called, the nervous, temperament. Such a constitution will readily wake in sudden emotions, and be characterized by ardent felling, quick passions, impetuous desires, and lively transient affections. There is a strong propensity to mirth and sport, and it easily habituates itself to a life of levity and gaiety. If sudden calamities occur, the sanguine temperament is readily overwhelmed in excessive grief, and melts in floods of tears for every affliction; but soon loses the deep sense of its sorrows, and springs again buoyant to new scenes of pleasure....
... There is a perpetual propensity in all its exercises to excess and exaggeration, to intense feeling and passionate excitement. The action is impulsive; the resolutions suddenly taken, and immediately executed, before unexpected difficulties, or long-resisting obstacles, are easily disconcerted and turned off in other directions.
This temperament is often found strongly marked in individual cases, and sometimes gives its controlling peculiarities to national character. It is the temperament widely prevalent in the French nation; and, though much modified in the form of its action, is still also the prevalent temperament of the Irish people.
Empirical Psychology -- Laurens Hickok, Julius Seelye