y he
must choose to do only that which shall not injure or affect the health
or comfort of his neighbors. This principle was not at first invoked to
prevent violations of laws of health, but rather to prevent the
inconvenience which might come to a neighbor or to the public at large
by some unreasonable though apparently legitimate use of individual
property. As an example we may mention the law of New York State
requiring each owner of property in the country to cut grass, weeds, and
brush along the highway twice each year. Although this interferes with
the right of the owner to have the land which belongs to him left as he
chooses, it is legal because of the greater convenience and comfort it
contributes to the larger number of persons traveling along the highway.

The state does not assume the right to interfere with the acts of
individuals so long as such acts affect only their own individual
well-being, but when those actions affect others, then the police power
of the state may be invoked. It is on this principle that the law
prohibits suicide, assuming that no man can live or die without
affecting the interests of other people. This is plainly so in the case
of the head of a family or in the case of a man upon whom others are
dependent and whose death removes their support and causes those
supported to become dependent upon the state or county. This principle
has been extended so as to include the cases where a method of living, a
lack of care, or even a mere appearance in public may adversely affect
the health of others in the same community. If, for example, a member of
a family has diphtheria or smallpox, and such a child is isolated so
that no danger of the spread of the disease exists, the state would not,
in general, insist upon the use of any preventive or curative
inoculation; but if a child with incipient diphtheria or whooping cough
goes to school where other children may be infected and the disease
spread, the state, acting through its Board of Education, would have a
perfect right to send the child home and prevent its enjoying school
privileges until recovery from the disease.

It is on this principle that the state says that no child in New York
State may attend school unless vaccinated, the law reading, "No child,
not vaccinated, shall be admitted into any of the public schools of the
state, and the trustees of the schools shall cause this provision of law
to be enforced." This law has been questi