PROBLEMS EMPU. 1 SIZED BY PRAGMATISM 41 1 



uses two digits, tlie digit on the right will stand for units, the digit on 

 the left for twos. The symbol 10 would now stand for two, the symbol 

 11 would stand for three, and so on. With the triadic system the places 

 would be used exactly as in our decadic system. In the first place 

 would be the units, in the next place to the left the threes, the third 

 place to the left the nines, the fourtli place the twenty-sevens, and so on. 

 Now all numbers could be written in any of these systems. In starting 

 with a new system, one could begin to perform additions, subtractions, 

 multiplications and divisions, as with the decadic system. The possi- 

 bility of an endless range of experiments, with mature persons, who, 

 while retaining all their present arithmetical knowledge, would be in- 

 stantly reduced to the position of young •children, so far as some of 

 the computations were concerned, all this makes an inquiry into the 

 psychology of simple deductions of this type a very attractive one. 

 Whoever wants to study psychology by becoming a little child has here 

 a place for a wide range of stud3\ 



