no reference to persons
_coming in_ from foreign countries to our own.

If, then, "migration," as here used, has reference only to persons
_going out_ from one state into another, the word "_importation_" is the
only one in the clause that is applicable to foreigners coming into our
country. This word "importation," then, being the only word that can
apply to persons coming into the country, it must be considered as
substantially synonymous with immigration, and must apply equally to
_all_ "persons," that are "imported," or brought into the country as
passengers. And if it applies equally to all persons, that are brought
in as passengers, it does not _imply_ that any of those persons are
slaves; for no one will pretend that this clause ever authorized the
state governments to treat as slaves _all_ persons that were brought
into the country as passengers. And if it did not authorize them to
treat all such passengers as slaves, it did not authorize them to treat
any of them as such; for it makes no discrimination between the
different "persons" that should be thus imported.

Again. The argument, that the allowance of the "importation" of
"persons," implies the allowance of property in such persons, would
imply a recognition of the validity of the slave laws of other
countries; for unless slaves were obtained by valid purchase
abroad--which purchase implies the existence and validity of foreign
slave laws--the importer certainly could not claim to import his slaves
as property; but he would appear, at the custom-house, as a mere pirate,
claiming to have his captures legalized. So that, _according to the
slave argument_, the simple use of the word "importation," in the
constitution, as applied to "persons," bound our government, not only to
the sanction and toleration of slavery in our own country, but to the
recognition of the validity of the slave laws of other countries.

But farther. The allowance of the "importation" of slaves, as such,
under this clause of the constitution, would imply that congress must
take actual, and even the most critical cognizance of the slave laws of
other countries; and that they should allow neither the mere word of the
person calling himself the owner, nor any thing short of the fullest and
clearest legal proof, according to the laws of those countries, to be
sufficient to enable him to enter his slaves, as property, at the
custom-house; otherwise any masters of vessels, from England or