1903.] STONEY—UNIVERSE OF REAL EXISTENCES. 125 
are in existence at any one time. But, in reality, these two acts 
of synthesis are now carried on by my mind and its synergos simul- 
taneously and with astonishing ease and promptitude; and it is 
probable that the gradually acquired power to make them was 
developed far passu in my ancestors at a very remote geological 
period. 
The instinct which impels us to assign a position in space to 
sensations affects our visual and tactual sensations most, including 
under the latter term our muscular sensations, as well as sensations 
of roughness, smoothness, resistance, hardness, softness, and some 
others. We also perceive it conspicuously in the allied sensations 
of tickling, warmth, coolness, pain, and several others. We localize 
with somewhat less precision our sensations of taste and smell: and 
of all our more conspicuous sensations sound is that which we least 
refer to a definite position. We have less power of doing so than 
many other animals who are furnished with ears which can be 
turned so as to distinguish the direction of sound; and far less 
power than some nocturnal insects who, by their feathery antenne, 
which are their auditory apparatus, are able to determine the direc- 
tion of a sound with a precision approaching that of eyesight.* In 
man there are but slender materials for the synthesis. 
It may make some parts of this and of the succeeding chapters 
clearer to give here a definition of the term odyect. This term 
might be applied to the objects of any hypothesis, z.¢., to the sup- 
posed existing things, which we are to suppose to be in existence 
so long as we are making use of the hypothesis. Thus, under the 
hypothesis made use of in Geometrical Optics, it would be intel- 
ligible to speak of rays in front of a mirror as having an odjective 
existence ; which would mean that they are the ‘ objects’ of that 
hypothesis, viz.: what we are to regard as being in existence under 
that hypothesis. But it is usual to make the terms object and 
objective more definite by restricting them to one particular hypoth- 
esis; and unless it is otherwise specified, they will be applied in 
the present essay only to the objects of that great objective hypoth- 
esis described in the present chapter, which by ‘the synthesis of 
the second order’ supplies us with what are popularly called the 
natural objects about us. 
1See Professor Alfred M. Mayer’s experiments on the mosquito, in which he 
satisfied himself that the male insect can determine the direction of a sound 
within an angle of 5° (Pitlosophical Magazine for November, 1874, p. 380), 
