Belief, then, is an attitude of mind in which we may find ourselves for good reasons, or for bad reasons, or for none at all; sometimes even slipping into it voluntarily or involuntarily when we know the situation is unreal; indeed, an attitude in which, in play or earnest, we pass our lives, unless something happens to arouse doubt or criticism. § 4. CAUSES AND GROUNDS OF BELIEF The source, direct or indirect, of all belief is perception. In perception must be included, for subjective studies, introspection; though being difficult to keep steady, to repeat and to compare with the observation of other minds, it carries less conviction. As to perception we say that “seeing is believing”; and, in fact, an object holds the eye in a way that vouches for its own reality; but, if we suspect that our eyes deceive us, reassurance comes with the handling of the thing. Belief has sometimes been discussed as if it were chiefly concerned with ideas or the relations of ideas; and systems of philosophy have sought justification in the coherence of ideas, with little or no regard (not to say with contempt) for the coherence of ideas with perceptions. But nearly the whole of every man’s life (savage or philosopher) passes in an attitude of unquestioning belief in the evidence of his senses; and it is thence that belief extends to ideas on a presumption of their representing reality. We know that a perception may be fallible, but perceptions and the comparison of perceptions in the long run overrule everything else; and experimental methods consist in taking precautions against the errors of perception, and in bringing every hypothesis to the test of perception. Further causes of belief are either Evidentiary, which (though often misleading) may generally be justified on reflection as raising some degree of probability, and which may, therefore, be called “grounds”; or Non-evidentiary, which (though very influential) cannot, on reflection, be justified as having any logical value, and are, therefore, causes only and not grounds.