Philosophy also changes with the change of history, and since history changes at every moment, philosophy at every moment is new. This can be observed even in the fact of the communication of philosophy from one individual to another by means of speech or writing. Change at once takes place in that transmission. When we have simply created again in ourselves the thought of a philosopher, we are in the same condition as he who has enjoyed a sonnet or a melody, by suiting his spirit to that of the poet or composer. But this does not suffice in philosophy. We may attain to ecstasy by the recitation of a poem or the execution of a piece of music, just as it is, without altering it anywhere. But it does not seem possible to possess a philosophic proposition, save when we have _translated_ it, as we say, _into our own language,_ when in reality, relying upon its results, we formulate new philosophic propositions and solve new problems that have presented themselves in our souls. For this reason no book ever completely satisfies us. Every book quenches one thirst, only to give us a new one. So true is this, that when we have finished reading or are in course of reading, we often regret that it is impossible to speak with the author. We are led to say, like Socrates in the _Phædrus,_[1] that written discourses are like pictures and do not answer questions, but always repeat what has already been said. Or we lose patience, like that Paduan professor of the fifteenth century, who, commenting on the jurist Paolo, and annoyed at the difficulties, exclaimed at a certain point: _"Iste maledictus Paulus tam obscure loquitur ut, si haberem eum in manibus, eum per capillos interrogarem!"_ But if instead of the dumb book, we had before us a living man, a Paolo obliged to be clear, the process would still be the same: his speech would be translated into our speech, his problem would arouse in our spirit our own problem. [Sidenote: _The perpetuity of change._]