surfaces are cold; just as by use we have all ceased to
be conscious that our faces are cold, even when out of doors. But though
in such children the sensations no longer protest, it does not follow
that the system escapes injury, any more than it follows that the
Fuegian is undamaged by exposure, because he bears with indifference the
melting of the falling snow on his naked body.

[7] We are not certain that the propagation of subdued forms of
constitutional disease through the agency of vaccination is not a part
cause. Sundry facts in pathology suggest the inference, that when the
system of a vaccinated child is excreting the vaccine virus by means of
pustules, it will tend also to excrete through such pustules other
morbific matters; especially if these morbific matters are of a kind
ordinarily got rid of by the skin, as are some of the worst of them.
Hence it is very possible--probable even--that a child with a
constitutional taint, too slight to show itself in visible disease, may,
through the medium of vitiated vaccine lymph taken from it, convey a
like constitutional taint to other children, and these to others.

[8] _Cyclopaedia of Practical Medicine_, vol. i. pp. 697, 698.

PART II

PROGRESS: ITS LAW AND CAUSE[1]

The current conception of Progress is somewhat shifting and indefinite.
Sometimes it comprehends little more than simple growth--as of a nation
in the number of its members and the extent of territory over which it
has spread. Sometimes it has reference to quantity of material
products--as when the advance of agriculture and manufactures is the
topic. Sometimes the superior quality of these products is contemplated:
and sometimes the new or improved appliances by which they are produced.
When, again, we speak of moral or intellectual progress, we refer to the
state of the individual or people exhibiting it; while, when the
progress of Knowledge, of Science, of Art, is commented upon, we have in
view certain abstract results of human thought and action. Not only,
however, is the current conception of Progress more or less vague, but
it is in great measure erroneous. It takes in not so much the reality of
Progress as its accompaniments--not so much the substance as the shadow.
That progress in intelligence seen during the growth of the child into
the man, or the savage into the philosopher, is commonly regarded as
consisting in the greater number of facts known and laws understood:
w