The content of it, the matter communicated, is chiefly thought and sentiment, in distinction from mere sensation or crude emotion. I do not venture to say that these latter cannot be shared, but certainly they play a relatively small part in the communicative life. Thus although to get one’s finger pinched is a common experience, it is impossible, to me at least, to recall the sensation when another person has his finger pinched. So when we say that we feel sympathy for a person who has a headache, we mean that we pity him, not that we share the headache. There is little true communication of physical pain, or anything of that simple sort. The reason appears to be that as ideas of this kind are due to mere physical contacts, or other simple stimuli, in the first instance, they are and remain detached and isolated in the mind, so that they are unlikely to be recalled except by some sensation of the sort originally associated with them. If they become objects of thought and conversation, as is likely to be the case when they are agreeable, they are by that very process refined into sentiments. Thus when the pleasures of the table are discussed the thing communicated is hardly the sensation of taste but something much subtler, although partly based upon that. Thought and sentiment are from the first parts or aspects of highly complex and imaginative personal ideas, and of course may be reached by anything which recalls any part of those ideas. They are aroused by personal intercourse because in their origin they are connected with personal symbols. The sharing of a sentiment ordinarily comes to pass by our perceiving one of these symbols or traits of expression which has belonged with the sentiment in the past and now brings it back. And likewise with thought: it is communicated by words, and these are freighted with the net result of centuries of intercourse. Both spring from the general life of society and cannot be separated from that life, nor it from them.