to the whole common sense conception of the world. If this thinker does not somehow magically reproduce external facts in his private mind, then is our faith vain, and we are all very miserable. It is astonishing how this, the most helpless abandonment of all philosophic thought, is constantly reiterated by certain of those who pretend to be philosophers. Can a threat scare us from philosophy? To get a sure foundation for our religion, we begin by asking how a man can really know the external world at all. We get as reply the threat that, unless we admit the knowledge of the external world, we must be in eternal doubt, and therefore wretched. To doubt this knowledge, we are told, would be to doubt all that makes life worth living. But it is just because we want to find a sure basis for what makes life worth living that we begin with this doubt. We are determined to get at the root of this matter, however bitter may be the evil that will befall us if our skepticism does not succeed in getting past this guarded gateway of philosophy. We persist in asking, all threats to the contrary notwithstanding, just how and why and in what sense the external world can be known to us, if indeed this conception itself of an external world is justly formed at all.
Yet we grant that the full force and need and bitterness of our problem may not be plain to the reader, unless he has first undertaken to examine with us at some length the philosophic character and consequences of this popular metaphysical conception of the external world. To get him to share
