My fellow-workers in this field know all too well the essential elements of that problem; I do not need here to go over already well-trodden ground; it will be sufficient to point out certain salient features of the position.

The main difficulty of our research lies in the fact that the Grail legend consists of a congeries of widely differing elements—­elements which at first sight appear hopelessly incongruous, if not completely contradictory, yet at the same time are present to an extent, and in a form, which no honest critic can afford to ignore.

Thus it has been perfectly possible for one group of scholars, relying upon the undeniably Christian-Legendary elements, preponderant in certain versions, to maintain the thesis that the Grail legend is ab initio a Christian, and ecclesiastical, legend, and to analyse the literature on that basis alone.

Another group, with equal reason, have pointed to the strongly marked Folk-lore features preserved in the tale, to its kinship with other themes, mainly of Celtic provenance, and have argued that, while the later versions of the cycle have been worked over by ecclesiastical writers in the interests of edification, the story itself is non-Christian, and Folk-lore in origin.

Both groups have a basis of truth for their arguments:  the features upon which they rely are, in each case, undeniably present, yet at the same time each line of argument is faced with certain insuperable difficulties, fatal to the claims advanced.

Thus, the theory of Christian origin breaks down when faced with the awkward fact that there is no Christian legend concerning Joseph of Arimathea and the Grail.  Neither in Legendary, nor in Art, is there any trace of the story; it has no existence outside the Grail literature, it is the creation of romance, and no genuine tradition.

On this very ground it was severely criticized by the Dutch writer Jacob van Maerlant, in 1260.  In his Merlin he denounces the whole Grail history as lies, asserting that the Church knows nothing of it—­which is true.

In the same way the advocate of a Folk-lore origin is met with the objection that the section of the cycle for which such a source can be definitely proved, i.e., the Perceval story, has originally nothing whatever to do with the Grail; and that, while parallels can be found for this or that feature of the legend, such parallels are isolated in character and involve the breaking up of the tale into a composite of mutually independent themes.  A prototype, containing the main features of the Grail story—­the Waste Land, the Fisher King, the Hidden Castle with its solemn Feast, and mysterious Feeding Vessel, the Bleeding Lance and Cup—­does not, so far as we know, exist.  None of the great collections of Folk-tales, due to the industry of a Cosquin, a Hartland, or a Campbell, has preserved specimens of such a type; it is not such a story as, e.g., The Three Days