grievous sin alone being necessary matter for that sacrament. There is
no downright cogent reason why a man might not do so. And yet, if he
neglected such ordinary means of grace as confession of venial sin,
having it within reach, month after month, no one, considering "the
sin which surrounds us," would expect that man to go without grievous
scathe. In mechanics, there are many machines that work prettily
enough in speculation and on paper, where the inventors do not
consider the difficulties of imperfect material, careless handling,
climate, and other influences, that render the invention of no
practical avail.

5. The safest use of Probabilism is in the field of property
transactions and of positive law. There is greatest risk of using it
amiss in remaining in a false religion. All turns upon the varying
amount of trouble involved in _moral diligence_ of enquiry, according
as the matter at issue is a point of mere observance or of vital
interest.

6. The point on which the probability turns must be the lawfulness or
unlawfulness of the action, not any other issue, as that of the
physical consequences. Before rolling boulder-stones down a hill to
amuse myself, it is not enough to have formed a probable opinion that
there is no one coming up. That would be Probabilism misapplied. The
correct enquiry is: Does any intrinsic reason or extrinsic authority
make the opinion probable, that it is lawful for mere amusement to
roll down rocks with any belief short of certainty that no one will be
crushed thereby? The probability, thus turned on to the lawfulness of
the action, breaks down altogether. This explanation, borne in mind,
will save much misapprehension.