Visionaries 
123 
objects actually seen. There is also a hybrid case which 
depends on fanciful visions fancifully perceived. The 
problems we have to consider are, on the one hand, those 
connected with “ induced” vision, and, on the other hand, 
those connected with the interpretation of vision, whether 
the vision be direct or induced. 
It is probable that much of what passes for hallucination 
proper belongs in reality to the hybrid case, being an illusive 
interpretation of some induced visual cloud or blur. I spoke 
of the ever-varying patterns in the optical field ; these, under 
some slight functional change, may become more con¬ 
sciously present, and be interpreted into fantasmai appear¬ 
ances. Many cases could be adduced to support this view. 
I will begin with illusions. What is the process by which 
they are established ? There is no simpler way of under¬ 
standing it than by trying, as children often do, to see 
“ faces in the fire,” and to carefully watch the way in which 
they are first caught. Let us call to mind at the same time 
the experience of past illnesses, when the listless gaze 
wandered over the patterns on the wall-paper and the 
shadows of the bed-curtains, and slowly evoked the appear¬ 
ances of faces and figures that were not easily laid again. 
The process of making the faces is so rapid in health that 
it is difficult to analyse it without the recollection of what 
took place more slowly when we were weakened by illness. 
The first essential element in their construction is, I believe, 
the smallness of the area covered by the glance at any 
instant, so that the eye has to travel over a long track 
before it has visited every part of the object towards which 
the attention is directed generally. It is as with a plough, 
that must travel many miles before the whole of a small 
field can be tilled, but with this important difference—the 
plough travels methodically up and down in parallel furrows ; 
the eye wanders in devious curves, with abrupt bends, and 
the direction of its course at any instant depends on four 
causes: (x) on the easiest sequence of muscular motion, 
speaking in a general sense, (2) on idiosyncrasy, (3) on the 
mood, and (4) on the associations current at the moment. 
The effect of idiosyncrasy is excellently illustrated by the 
“Number-Forms,” where we observe that a very special 
sharply-defined track of mental vision is preferred by each