Now what has experimental science to say about the conscience? It does _not_ say that it is the voice of God--a fact by no means calculated to disturb those who remember that physical investigation is not concerned with such speculations. Half the mischief and misunderstandings which occur over these border questions, which are, so to speak, under two jurisdictions, arise from our forgetting in what capacity and by what principles certain well-known scientific men have made pronouncements on matters such as conscience, morality and religion. There are two sides to them, the physical and the hyper-physical or metaphysical. And here it may not be amiss to offer a suggestion that one should mistrust that parrot cry so often heard from men who speak most confidently about that which they know least, that metaphysic is synonymous with unreality, or in plainer words, moonshine. A very little reflection will be sufficient to satisfy us that without the aid of conceptions higher than those of sense-experience--and that is all the word metaphysic means--it would be absolutely impossible to formulate a single scientific generalisation. What is the very concept of law, or system, but a metaphysical idea? To cease to be metaphysical would be to cease to be rational, to have no higher or wider conceptions than those of a dog. Hence, like M. Jourdain, who had been talking prose all his life without knowing it, some of our most daring anti-metaphysicians have been philosophising by the very method they had in their ignorance so contemptuously denounced.