There remains the consideration of the second part of the double problem which was formulated above--the method of interpretation. The native method is to believe the scholiasts' explanations, which often are fanciful and, in all important points, totally unreliable; since the Hindu commentators lived so long after the period of the literature they expound that the tradition they follow is useful only in petty details. From a modern point of view the question of interpretation depends mainly on whether one regard the Rig Veda as but an Indic growth, the product of the Hindu mind alone, or as a work that still retains from an older age ideas which, having once been common to Hindu and Iranian, should be compared with those in the Persian Avesta and be illustrated by them. Again, if this latter hypothesis be correct, how is one to interpret an apparent likeness, here and there, between Indic and foreign notions,--is it possible that the hymns were composed, in part, before the advent of the authors into India, and is it for this reason that in the Rig Veda are contained certain names, ideas, and legends, which do not seem to be native to India? On the other hand, if one adopt the theory that the Rig Veda is wholly a native work, in how far is he to suppose that it is separable from Brahmanic formalism? Were the hymns made independently of any ritual, as their own excuse for being, or were they composed expressly for the sacrifice, as part of a formal cult? Here are views diverse enough, but each has its advocate or advocates. According to the earlier European writers the Vedic poets are fountains of primitive thought, streams unsullied by any tributaries, and in reading them one quaffs a fresh draught, the gush of unsophisticated herdsmen, in whose religion there is to be seen a childlike belief in natural phenomena as divine forces, over which forces stands the Heaven-god as the highest power. So in 1869 Pfleiderer speaks of the "primeval childlike naïve prayer" of Rig Veda vi. 51. 5 ("Father sky, mother earth," etc.);[15] while Pictet, in his work _Les Origines Indo-Européennes_, maintains that the Aryans had a primitive monotheism, although it was vague and rudimentary; for he regards both Iranian dualism and Hindu polytheism as being developments of one earlier monism (claiming that Iranian dualism is really monotheistic). Pictet's argument is that the human mind must have advanced from the simple to the complex! Even Roth believes in an originally "supreme deity" of the Aryans.[16] Opposed to this, the 'naïve' school of such older scholars as Roth, Müller,[17] and Grassmann, who see in the Rig Veda an ingenuous expression of 'primitive' ideas, stand the theories of Bergaigne, who interprets everything allegorically; and of Pischel and Geldner, realists, whose general opinions may thus be formulated: The poets of the Rig Veda are not childlike and naïve; they represent a comparatively late period of