The enjoyment that moves us to laughter must, it is evident, amount to gladness or joy. And this means, first of all, that the pleasurable consciousness must come in the form of a large accession, and, for a moment at least, be ample, filling soul and body. As the expression “good spirits” suggests, the organic processes during such states of joyousness are voluminous and well marked. As a part of this heightened tide of vital activity, we have the characteristic motor expression of the gladsome mind, the movement of the limbs, the shouting and the laughing. Not all risings of the vital tide, however, produce laughter. Gentle and gradual augmentations of the sense of well-being {72} and happiness hardly tend to stir the muscles concerned. The joyous outburst marks a _sudden_ accession of happy consciousness. It has something of the character of a violent flooding of the spirit and the corresponding bodily conduits. There is a negative condition, also, to which it may not be superfluous to allude. The flood-like rise of the happy mood which is to produce laughter must not be accompanied by any further demand on the attention. A girl reading a first love letter from the man whom her heart has chosen will be glad, and will grow gladder by leaps and bounds. But the fulness of laughter will not come while unread words still claim the eye. The laughter of joy is most noticeable, I think, under two sets of conditions. Of these the first is the situation of release from external restraint. The wild jubilant gladness of boys as they rush out of school, provided that they have the requisite reserve fund of animal spirits, is the stock example of this sort of laughter. The explosion seems here to be a way of throwing off the constraint and the dulness of the classroom, and getting a deep breath of the delicious sense of restored liberty. So far as the outflow of good spirits is thus connected with an escape from a serious and difficult attitude—strenuous application of the energies of mind and body in work—it is plainly analogous to the nervous laughter already considered.