Perhaps the more northern type left all that behind in its youth. The rugged, angular character which appreciates force better than harmony, the strong intellect which delights in forethought and calculation, the less impressibility, reaching stolidity in the uneducated, are its well-known traits. If in such a character generosity is less prompt, and there is but little chivalry, there is persistency and unwavering fidelity, not readily interrupted by the lightning of passion or the dark surmises of an active imagination. All these peculiarities appear to result, _first_, from different degrees of quickness and depth in appreciating impressions from without; and, _second_, from differing degrees of attention to the intelligent judgment in consequent action. (I leave conscience out, as not belonging to the category of inherited qualities.) The first is the basis of an emotional nature, and the predominance of the second is the usual indication of maturity. That the first is largely dependent on an impressible condition of the nervous system can be asserted by those who reduce their nervous centers to a sensitive condition by a rapid consumption of the nutritive materials necessary to the production of thought-force, and perhaps of brain-tissue itself, induced by close and prolonged mental labor. The condition of over-work, though but an imitation of immaturity, without its joy-giving nutrition, is nevertheless very instructive. The sensitiveness, both physically, emotionally and morally, is often remarkable, and a weakening of the understanding is often coincident with it. It is necessary here to introduce a caution, that the meaning of the words high and low be not misunderstood. Great impressibility is an essential constituent of many of the highest forms of genius, and the combination of this quality with strong reflective intelligence, constitutes the most complete and efficient type of mind—therefore the highest in the common sense. It is not, however, the highest—or extremest—in an evolutional sense, it is not masculine, but hermaphrodite; in other words, its _kinetic_ force exceeds its _bathmic_.[49] It is therefore certain that a partial diminution of bathmic vigor is an advantage to some kinds of intellect. Footnote 49: _Bathmic force_ is analogous to the _potential_ force of chemists, but is no doubt entirely different in its nature. It is converted into active energy or _kinetic_ force only during the years of growth: it is in large amount in _acceleration_, in small amount in _retardation_.