Let us tarry a while over the point which unites the three groups, which is common to the three mechanisms of tongue slips. Fortunately, that is unmistakable. In the first two groups the interfering tendency is recognized by the speaker; in the first there is the additional fact that it showed itself immediately before the slip. In both cases, however, _it was suppressed. The speaker had made up his mind not to convert the interfering tendency into speech and then the slip of the tongue occurred; that is to say, the suppressed tendency obtains expression against the speaker's will, in that it changes the expression of the intention which he permits, mixes itself with it or actually puts itself in its place._ This is, then, the mechanism of the tongue slip. From my point of view, I can also best harmonize the processes of the third group with the mechanism here described. I need only assume that these three groups are differentiated by the different degrees of effectiveness attending the suppression of an intention. In the first group, the intention is present and makes itself perceptible before the utterance of the speaker; not until then does it suffer the suppression for which it indemnifies itself in the slip. In the second group the suppression extends farther. The intention is no longer perceptible before the subject speaks. It is remarkable that the interfering intention is in no way deterred by this from taking part in the causation of the slip. Through this fact, however, the explanation of the procedure in the third group is simplified for us. I shall be so bold as to assume that in the error a tendency can manifest itself which has been suppressed for even a longer time, perhaps a very long time, which does not become perceptible and which, therefore, cannot be directly denied by the speaker. But leave the problem of the third group; from the observation of the other cases, you most draw the conclusion that _the suppression of the existing intention to say something is the indispensable condition of the occurrence of a slip_.