homogeneity even of this quality of "energy" or "go." A person without
restraint, without intellectual conscience, without critical faculty,
may write and jabber and go to and fro and be here and there, simply
because every impulse is obeyed so soon as it arises. Another person
may be built upon an altogether larger scale of energy, but may be
deliberate, concentrated, and fastidious, bent rather upon truth and
permanence than upon any immediate quantitative result, and may appear
to any one but an extremely penetrating critic, as inferior in energy
to the former. So far as our knowledge goes at present, what is
popularly known as "energy" or "go" is just as likely to be a certain
net preponderance of a varied miscellany of impulsive qualities over a
varied miscellany of restraints and inhibitions, as it is to prove a
simple indivisible quality transmissible intact. We are so profoundly
ignorant in these matters, so far from anything worthy of the name of
science, that one view is just as permissible and just as untrustworthy
as the other.

Even the qualification of "health" is not sufficient. A thoughtless
person may say with the most invincible air, "Parents should, at any
rate, be healthy," but that alone is only a misleading vague formula
for good intentions. In the first place, there is every reason to
believe that transitory ill-health in the parent is of no consequence
at all to the offspring. Neither does acquired constitutional ill-
health necessarily transmit to a child; it may or it may not react upon
the child's nutrition and training, but that is a question to consider
later. It is quite conceivable, it is highly probable, that there are
hereditary forms of ill-health, and that they may be eliminated from
the human lot by discreet and restrained pairing, but what they are and
what are the specific conditions of their control we do not know. And
furthermore, we are scarcely more certain that the condition of