416 Wisconsin Academy of Sciences, Arts, and Letters. 
the excellent reason that it is not in my mind. That is, in my 
attempted judgment there is a void. 
Suppose now that I come to you with this void alone, without 
surrounding elements, and a,sk you to fill it. In the beginning, 
says the Scripture, “The earth was without form and void.’ 7 
Likewise what I bring you is not only void, but also without 
form. I offer you vacant mental space without its contours. 
To fill this space, however, as I would have it filled, not every 
form of thought-material can, be used; nor is there any universal 
stop-gap for mental emptiness—no answer suitable to every 
question. To enable you to* choose aright, I must, to speak with 
the utmost objectivity, establish for you the contours of the void. 
This I do by imitating the fantastic building of the cannon. 
Around a hole I put some iron. About the mental void I gather 
elements, which serve as boundaries. I establish, so to speak, 
the edges of the void—in other words, its mental environment. 
This environment consists of those thought-members which al¬ 
ready are in mind. The void and this environment being then 
coterminal, the existing thought-members may be said to furnish 
the boundaries of the void. 
How the void is not, of course, what I wish to obtain from 
you. But, as the void must be exactly filled, its boundaries are 
those of the element which is to fill it—the desired element— 
the element which the question aims; to obtain; and these bound¬ 
aries—or ideas which I already have—the question does ex¬ 
press. Accordingly I may say that in asking you a question— 
that is, in asking you for a void-filler—I give you the void-filler’s 
boundaries. 
How boundaries are in the strictest sense a definition. We 
are then prepared to learn that, when an interrogative judg¬ 
ment is formed, ideas already found will be used as definition 
of an, idea yet to be found. Thus, given the uncompleted 
thought expressed by “-killed Lincoln,” it is quite impossi¬ 
ble for you to think of the required thought-element, except so 
far as you be guided by a definition (description or determina¬ 
tion). But the only definition I can give you is that afforded 
by “killed Lincoln.” That is, the mental desideratum must be 
distinguished from other thinkables by its fitting what may be 
summed up as “Lincoln-killing.”* 
*With a little anticipation I can further indicate that ideas already 
in the questioner’s mind are offered and accepted, as defining the idea 
