466 FRAGMENTS Off SCIENCE. 
faculties of perception and of action ' vanish; at every 
relaxation of pressure they are restored. Where, during 
the intervals of pressure, is the perceiving power? I once 
had the discharge of a large Leyden battery passed unex- 
pectedly through me: I felt nothing, but \vassirnply blotted 
out of conscious existence for a sensible interval. Where 
was my true self during that interval? Men who have 
recovered from lightning-stroke have been much longer in 
the same state; and indeed in cases of ordinary concussion 
of the brain, days may elapse during which no experience 
is registered in consciousness. Where is the man himself 
during the period of insensibility? You may say that I 
beg the question when I assume the man to have been 
unconscious, that he was really conscious all the time, and 
has simply forgotten what had occurred to him. In reply 
to this, I can only say that no one need shrink from the 
worst tortures that superstition ever invented, if only so 
felt and so remembered. I do not think your theory of 
instruments goes at all to the bottom of the matter. A 
telegraph operator has his instruments, by means of which 
he converses with the world; our bodies possess a nervous 
system, which plays a similar part between the perceiving 
power and external things. Cut the wires of the operator, 
break his battery, demagnetize his needle; by this means 
you certainly sever his connection with the world; but, 
inasmuch as these are real instruments, their destruction 
does not touch the man who uses them. The operator sur- 
vives, and he knows that he survives. What is there, I 
would ask, in the human system that answers to this con- 
scious survival of the operator when the battery of the brain 
is so disturbed as to produce insensibility, or when it is 
destroyed altogether? 
"Another consideration, which you may regard as 
slight, presses upon me with some force. The brain may 
change from health to disease, and through such a change 
the most exarnplary man may be converted intoa debauchee 
or a murderer. My very noble and approved good master 
had, as you know, threatenings of lewd ness introduced into 
his brain by his jealous wife's philter; and sooner than 
permit himself to run even the "risk of yielding to these 
base promptings he slew himself. How could the hand of 
Lucretius have been thus turned against himself if the real 
Lucretius remained as before? Can the brain or can it 
