e of the murder, and
whether he was there for the purpose of aiding and abetting
Crowninshield, the actual murderer; the question whether his presence
outside the house would make him liable as a principal in the crime was
a question of law. This distinction between questions of fact and
questions of law is one of the foundation principles of the common law.
From the very beginning of the jury system, when the jury consisted of
neighbors who found their verdict from their own knowledge of the case,
to the present day when they are required carefully to purge their minds
of any personal knowledge of the case, the common law has always held
that in the long run questions of fact can best be settled by average
men, drawn by lot from the community. Questions of law, on the other
hand, need learning and special training in legal reasoning, for the
common law depends on continuity and consistency of decision; and a new
case must be decided by the principles which have governed like cases in
the past.

Nevertheless, these principles, which are now embodied in an enormous
mass of decisions by courts all over the English-speaking world, are in
essence a working out into minute discriminations of certain large
principles, which in turn are merely the embodiment of the practical
rules under which the Anglo-Saxon race has found it safest and most
convenient to live together. They settle in each case what, in view of
the interests of the community as a whole and in the long run, and not
merely for the parties now at issue, is the most convenient and the
justest thing to do. Mr. Justice Holmes, of the Supreme Court of the
United States, wrote before his appointment to that bench:

"In substance the growth of the law is legislative. And this in a deeper
sense than that what the courts declare to have always been the law is
in fact new. It is legislative in its grounds. The very considerations
which judges most rarely mention, and always with an apology, are the
secret roots from which tine law draws all the juices of life. I mean of
course considerations of what is expedient for the community concerned.
Every important principle which is developed by litigation is in fact
and at bottom the result of move or less definitely understood views of
public policy; most generally, to be sure, under our practices and
traditions, the unconscious result of instinctive preferences and
inarticulate convictions, but none the less traceable to view