VERTEBRATES: BACKBONE AND BRAIN
The advance of vertebrates from fish through amphibia and reptiles to
mammals.-The development of skeleton, appendages, circulatory and
respiratory systems, and brain. -Mammals: The oviparous monotremata.
-Marsupials.-Placental mammals.-Development of the placenta.-Prim-
ates.-Arboreal life and the development of the hand.-Comparison of man
with the highest apes. -Recapitulation of the history of man's origin and
development.-The sequence of dominant functions.
THE HISTORY OF MENTAL DEVELOPMENT AND ITS
SEQUENCE OF FUNCTIONS
Mode of investigation.- Intellect. - Sense-perceptions.-Association. —
Inference and understanding.-Rational intelligence.-Modes of mental or
nervous action.-Reflex action, unconscious and comparatively mechanical.
-Instinctive action: The actor is conscious, but guided by heredity.—In-
telligent action.-The actor is conscious, guided by intelligence resulting
from experience or observation.-The will stimulated by motives.-Appe-
tites.-Fear and other prudential considerations.-Care for young and love
of mates.-The dawn of unselfishness.-Motives furnished by the rational
intelligence: Truth, right, duty.-Recapitulation: The will, stimulated by
ever higher motives, is finally to be dominated by unselfishness and love
of truth and righteousness.-These rouse the only inappeasable hunger,
and are capable of indefinite development.-Strength of these motives.—
Their complete dominance the goal of human development.
NATURAL SELECTION AND ENVIRONMENT
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The reversal of the sequence of functions leads to extermination, degen-
eration, or, rarely, to stagnation.-Natural selection becomes more un-
sparing as we go higher.-Extinction.-Severity of the struggle for life.—
Environment one.-But lower animals come into vital relation with but a
small part of it.-It consists of a myriad of forces, which, as acting on a