have never suffered?

Those who are acquainted only with a single group are apt to be
ready with solutions. Thus I have heard the mortality of the
Maoris attributed to their change of residence--from fortified
hill-tops to the low, marshy vicinity of their plantations. How
plausible! And yet the Marquesans are dying out in the same houses
where their fathers multiplied. Or take opium. The Marquesas and
Hawaii are the two groups the most infected with this vice; the
population of the one is the most civilised, that of the other by
far the most barbarous, of Polynesians; and they are two of those
that perish the most rapidly. Here is a strong case against opium.
But let us take unchastity, and we shall find the Marquesas and
Hawaii figuring again upon another count. Thus, Samoans are the
most chaste of Polynesians, and they are to this day entirely
fertile; Marquesans are the most debauched: we have seen how they
are perishing; Hawaiians are notoriously lax, and they begin to be
dotted among deserts. So here is a case stronger still against
unchastity; and here also we have a correction to apply. Whatever
the virtues of the Tahitian, neither friend nor enemy dares call
him chaste; and yet he seems to have outlived the time of danger.
One last example: syphilis has been plausibly credited with much
of the sterility. But the Samoans are, by all accounts, as
fruitful as at first; by some accounts more so; and it is not
seriously to be argued that the Samoans have escaped syphilis.

These examples show how dangerous it is to reason from any
particular cause, or even from many in a single group. I have in
my eye an able and amiable pamphlet by the Rev. S. E. Bishop: 'Why
are the Hawaiians Dying Out?' Any one interested in the subject