s has taken place he would thereby
show his latent belief in moral progress. For no man would take the
trouble to deny moral progress unless he believed that the world would
in some way be made better by his denial. He would not even trouble to
come to a private conclusion in the matter unless he believed that his
private conclusion was something to the good. In that sense perhaps we
may say that moral progress is proved, for the best proof of any belief
is that it remains indispensable to the life we have to live. But the
appeal to experience would not prove it--and for this reason. A
progressive world is a world which not only makes gains, but _keeps_ its
gains when they are made. If the Kingdom of Heaven were to become a
fact to-morrow, that of itself would not prove progress, if you admit
the possibility that the world might hereafter retreat from the position
it had won. That possibility you could never rule out--except by an
appeal to faith. A world which attained the goal and then lost it would
be a greater failure, from the point of view of moral progress, than one
which never attained the goal at all. The doctrine that the gains of
morality can never be lost is widely held; but it does not rest on a
philosophic or a scientific basis. As Hume taught long ago, you cannot
infer an infinite conclusion from finite data--and in this case the
conclusion is infinite and the data are finite. They are not only finite
but various: some pointing one way, some another.

Finally we cannot prove moral progress by appeal to any objective
standard, such as the amount of happiness existing in the world at
successive dates. Suppose you were able to show that, up to date, the
amount of happiness in the world has shown a steady increase until it
has reached the grand sum total now existing. Now suppose that you were
transferred to another planet where the conditions were the exact
opposite: where the inhabitants ages ago started with the happiness we
now possess, and gradually declined until, at the present moment, they
are no happier than the human race was at the first stage of its career.
Now add together the totals of happiness for both your worlds, the
ascending world which starts with the minimum and ends with the maximum,
the declining world which starts with the maximum and ends with the
minimum. The grand totals in both cases are exactly the same. So far as
the total result is concerned, the declining world has just as much