als.

LECTURE VIII.

THE LEGAL ASPECTS OF INSANITY.

In our last lecture, gentlemen, we considered the nature and causes of
delusional insanity. We saw that its essence lies in mistaking
imaginations for realities with a firmness of conviction which no
argument to the contrary can shake. The reasoning of the insane man may
be logically faultless, we said, but he reasons from false premises
supplied to him by the phantasms of a diseased imagination. The cause of
the disease I showed to lie in an abnormal action of the brain, which is
the storehouse of the phantasms or brain-pictures. And this abnormal
action may itself proceed either from a local lesion of the brain, or
from a sympathetic affection due to indisposition in other parts of the
human body. I finished by examining the responsibility of an insane man
for his actions, and arrived at this practical conclusion, that a victim
of delusional insanity should not be held responsible for any acts which
he insanely thinks right, but should be held responsible for all his
other human acts.

I. This teaching of psychological and ethical science is to-day the
received rule of action followed by the courts of justice in England and
the United States. Sound philosophy and positive law are in perfect
agreement on this subject. But it was not so a hundred years ago. It is
wonderful to us now how strange and erroneous were the views of insanity
formerly entertained by English jurists. For instance, when, in 1723,
Arnold was tried for shooting at Lord Onslow, the instruction given to
the court was that, for one to be exempt from punishment in such a case,
"it must be a man that is totally deprived of his understanding and does
not know what he is doing, no more than an infant, than a brute or a
wild beast." On such a theory, very few lunatics indeed would be
acquitted; few ever are so totally demented.

The first jurist that pointed out the true test of insanity was Lord
Erskine, who, in 1800, when Hudfield was tried for shooting at the king,
delivered a celebrated speech, in which he maintained that the real test
of insanity was in delusion: if delusion existed the man was insane;
else, he was not insane. The deluded man, he said, might reason with
admirable logic from his false principles; he was nevertheless demented
if he mistook his imaginations for realities, and did so irresistibly
and persistently.

Erskine's test has been, from that time on, followed in t