366 THE CAUSES OF THE XI 
to make an induction from; you generalise the 
facts, and you expect to find sourness in apples 
where you get hardness and greenness. You found 
upon that a general law, that all hard and green 
apples are sour; and that, so far as it goes, is a 
perfect induction. Well, having got your natural 
law in this way, when you are offered another 
apple which you find is hard and green, you say, 
“ All hard and green apples are sour; this apple 
is hard and green, therefore this apple is sour.” 
That train of reasoning is what logicians call a — 
syllogism, and has all its various parts and terms, 
—its major premiss, its minor premiss, and its 
conclusion. And, by the help of further reason- 
ing, which, if drawn out, would have to be exhibited 
in two or three other syllogisms, you arrive at your 
final determination, “I will not have that apple.” 
So that, you see, you have, in the first place, 
established a law by induction, and upon that you 
have founded a deduction, and reasoned out the 
special conclusion of the particular case. Well 
now, suppose, having got your law, that at some 
time afterwards, you are discussing the qualities 
of apples with a friend : you will say to him, “ It is 
a very curious thing,—but I find that all hard and. 
green apples are sour!” Your friend says to you, 
“But how do you know that?” You at once 
reply, “Oh, because I have tried them over and — 
over again, and have always found them to be so.” 
Well, if we were talking science instead of common 
