Prof. Cattell found he could get no results by this method, and reverted to one used by observers previous to Wundt and which Wundt had rejected. This is the _einfache Wahlmethode_, as Wundt calls it. The reacter awaits the signal and reacts if it is of one sort, but omits to act if it is of another sort. The reaction thus occurs after discrimination; the motor impulse cannot be sent to the hand until the subject knows what the signal is. Reacting in this way, Prof. Cattell found the increment of time required for distinguishing a white signal from no signal to be, in two observers, 0.030 and 0.050; that for distinguishing one color from another was similarly 0.100 and 0.110; that for distinguishing a certain color from ten other colors, 0.105 and 0.117; that for distinguishing the letter A in ordinary print from the letter Z, 0.142 and 0.137; that for distinguishing a given letter from all the rest of the alphabet (not reacting until that letter appeared), 0.119 and 0.116; that for distinguishing a word from any of twenty-five other words, from 0.118 to 0.158 sec. --the difference depending on the length of the words and the familiarity of the language to which they belonged. Prof. Cattell calls attention to the fact that the time for distinguishing a word is often but little more than that for distinguishing a letter: "We do not, therefore," he says, "distinguish separately the letters of which a word is composed, but the word as a whole. The application of this in teaching children to read is evident." He also finds a great difference in the time with which various letters are distinguished, E being particularly bad.