For man can be said to be composed of two collectivities and an individualizing trunk. Down below the instincts, the roots of his being, plunge into the earth this tree had packed in its inside when it got moving. His roots are plural. They ramify far into the blood plasma of his ancestors, his whole people in fact. Up above his intuition forms a no less real if no more visible ramification of branches and twigs around his head. . . . And, of course, you will remember the most important function of the foliage: the work of the chlorophyll in the leaves, transmuting the energy of the sun into chemical energy. So the foliage of the human tree transmutes the intuitional energy that it receives from the source of all mind-light into mental energy; and persons of highly developed foliage are rich in not precisely intellect but that faculty above the intellect which feeds it with light-energy.

Salvatore de Madariaga, Portrait of a Man Standing

There is an impressive quietness in animals. There they are, set four-square within their species, content, unseeking, unconcerned; each living according to its nature as it found it at birth, and asking no questions. All this conforms with the horizontal posture. The animal is at rest, in a state of permanent equilibrium. Not so man. His erect posture sets going in him an urge upwards that is doomed to remain forever unassuaged. Ambition, perfectionism, heroism, holiness, knowledge, mastery, rebellion this urge upwards will take on many a color, name, shape, or trend; it will always act as a force stretching the self to its utmost and seeking the All-Highest.

Salvatore de Madariaga, Portrait of a Man Standing