We will therefore leave the analysis of errors here. But may I remind you of one thing more: keep in mind, as a prototype, the manner in which we have treated these phenomena. You can see from these examples what the purposes of our psychology are. We do not wish merely to describe the phenomena and to classify them, but to comprehend them as signs of a play of forces in the psychic, as expressions of tendencies striving to an end, tendencies which work together or against one another. We seek a dynamic conception of psychic phenomena. The perceived phenomena must, in our conception, give way to those strivings whose existence is only assumed. Hence we will not go deeper into the problem of errors, but we can still undertake an expedition through the length of this field, in which we will reëncounter things familiar to us, and will come upon the tracks of some that are new. In so doing we will keep to the division which we made in the beginning of our study, of the three groups of tongue slips, with the related forms of pen slips, misreadings, mishearings, forgetfulness with its subdivisions according to the forgotten object (proper names, foreign words, projects, impressions), and the other faults of mistaking, mislaying and losing objects. Errors, in so far as they come into our consideration, are grouped in part with forgetfulness, in part with mistakes. We have already spoken in such detail of tongue slips, and yet there are still several points to be added. Linked with tongue slips are smaller effective phenomena which are not entirely without interest. No one likes to make a slip of the tongue; often one fails to hear his own slip, though never that of another. Tongue slips are in a certain sense infectious; it is not at all easy to discuss tongue slips without falling into slips of the tongue oneself. The most trifling forms of tongue slips are just the ones which have no particular illumination to throw on the hidden psychic processes, but are nevertheless not difficult to penetrate in their motivation. If, for example, anyone pronounces a long vowel as a short, in consequence of an interference no matter how motivated, he will for that reason soon after lengthen a short vowel and commit a new slip in compensation for the earlier one. The same thing occurs when one has pronounced a double vowel unclearly and hastily; for example, an "eu" or an "oi" as "ei." The speaker tries to correct it by changing a subsequent "ei" or "eu" to "oi." In this conduct the determining factor seems to be a certain consideration for the hearer, who is not to think that it is immaterial to the speaker how he treats his mother tongue. The second, compensating distortion actually has the purpose of making the hearer conscious of the first, and of assuring him that it also did not escape the speaker. The most frequent and most trifling cases of slips consist in the contractions and foresoundings which show themselves in inconspicuous parts of speech.