Vicious as such a process would be, it is not so faulty as that of confounding the proper methods and attestations of speculative and practical truth.[166] Our human consciousness must in _both_ cases give our data. We have to ask and obtain its answers,--but, in the two different spheres of knowledge, we must frame our interrogatories differently, and expect assurances differing not in _degree_ of certainty, but in _kind_;--in _value_ to human action;--and in the _mode_ of their deliverance. We inquire into Speculative truth by _analysing_ it, until we arrive at undemonstrable axioms which assert their own validity. We assure ourselves that Practical principles are true by following them in their _synthetic_ growth. Do they spring from a maxim we find ourselves urged by our own nature to accept,--and the opposite of which we cannot but broadly reject;--and do they really _work_ in the world,--exert an ennobling influence within their own domain, and intertwine themselves with the other truths and activities of our human life? If so, we may be assured of their vitality and their certitude. We know them, in short, by their stringency,--and by a happy experience of their power. Consequently, our knowledge ought to grow and strengthen, as our human age and the world's age both roll on. Practical truth, thus tried and acknowledged, is indeed the silver thread which leads us always. Some shrink from trusting it when stretched across the grave; yet, without it, all beyond is lost in haze, and our present life becomes enigmatical and self-contradictory. Let us then apply the tests (found valid in their own practical sphere) to the case of our belief in a Supernatural and supreme Power. But, that we may do so with more evident effect, it will be well to place in juxtaposition with it _another_ powerful belief, and our progress will be rendered easier if we fix upon one which has already been, in part at least, under discussion. Nothing seems better fitted for this purpose, than what Professor Masson calls "the paramount fact," resulting alike to Hamilton and to Mill,--the universal persuasion in men of their own existence, as beings distinct from, but related to, an external world around them. It will be observed that, thus described, the fact is of a most concrete sort,--our inner reality in relation to an outer reality,--just as believing in a Supreme Being we believe in a Power that holds solemn relations to our individual selves and to our common Humanity. We have therefore to observe the impression made upon our human endowment of practical Reason, when looking face to face at these two fact-beliefs, which for brevity's sake we shall call the _Natural_ and the _Supernatural_.