Spontaneous replies provide a special proof of this ability to form independent thoughts, and is found both among horses and dogs. Such a reply is indeed the sudden and evident utterance of some thought, and of a thought which--to it--transcends all other thoughts at the moment: one which regardless of all other questions which may at the time be put to it, looms largest, and the animal will therefore utter this remark, asked or unasked--and quite independently of any question, but more after the manner of "making an observation." Such a thought may have nothing to do with the subject in hand, and persons who are participating in this conversation _a deux_, can only arrive at the inference of ideas after having carefully thought the matter over--it may also be that they will fail to see any association of ideas at all. Now, it is indisputable that such replies belong to the most important category--for they may serve as proofs to those who themselves have not worked with animals for any length of time, and who, therefore, cannot become sincerely convinced as to the truth of the matter by travelling the longer road of personal test and experience. The teacher of any horse or dog of good parts does not need this proof: there are thousands of small instances which in their sum total prove important--trivial and uncertain though each one may be, when regarded by itself. It would be difficult to know how to convey these to anyone in words: glances, movements, a certain "live appeal"--it would require a poet to catch and fix--in short--to idealize--telling us the true inwardness, so that we might indeed comprehend ... and even then he would, I fear, make for weariness, when grappling with what well may seem interminable.[20] Here are a few examples: [20] The poet, Hans Mueller, has touched most eloquently on the power to think latent in animals in his book, "Die Kunst sich zu freuen." 16 May, 1916: Lola was doing arithmetic and I had given her some new sums. Suddenly, instead of calculating, she gives--"not reckon." I asked her the date, she replied "16"--adding of herself "too little to eat." In the course of the afternoon, Lola, who had gone with me to tea at B. L.'s, was shown some pictures: "What is that?" she was asked. "re," (ein Reh = a deer) "segen haus, ich wenig nur arbeite." "Will you do more here?" "yes." "Arithmetic?" "Yes, yes!" (very joyfully) and excellent replies followed.