The answer to this question, as it seems to us, is hidden in the obscurity of the religious communities. We cannot, however, go so far as to agree with those who would cut the gordian knot by asserting dogmatically that the ascetic communities in Syria and Egypt were founded by these Buddhist propagandists. Already even in Greece itself were not only Pythagorean but even prior to them Orphic communities, for even on this ground we believe that Pythagoras rather developed what he found already existing, than that he established something entirely new. And if they were found in Greece, much more then is it reasonable to suppose that such communities already existed in Syria, Arabia, and Egypt, whose populations were given far more to religious exercises than the sceptical and laughter-loving Greeks.
It is, however, credible that in such communities, if anywhere, Buddhist propaganda would find an appreciative and attentive audience; but even so it is remarkable that they have left no distinctly direct trace of their influence. Nevertheless, both by the sea way and by the great caravan route there was an ever open line of communication between India and the Empire of the successors of Alexander; and it is even permissible to speculate, that if we could recover a catalogue of the great Alexandrian library, for instance, we should perchance find that in it Indian MSS. were to be found among the other rolls and parchments of the scriptures of the nations.
Indeed, there are phrases in the oldest treatises of the Trismegistic Hermetic literature which can be so closely paralleled with phrases in the Upaniṣhads and in the Bhagavad Gītā, that one is almost tempted to believe that the writers had some acquaintance with the general contents of these Brāhmanical scriptures. The Trismegistic literature had its genesis in Egypt, and its earliest deposit must be dated at least in the first century a.d., if it cannot even be pushed back earlier. Even more striking is the similarity between the lofty mystic metaphysic of the Gnostic doctor Basilides, who lived at the end of the first and beginning of the second century a.d., and Vedāntic ideas. Moreover, both the Hermetic and the Basilidean schools and their immediate predecessors were devoted to a stern self-discipline and deep philosophical study which would make them welcome eagerly any philosopher or mystic student who might come from the far East.
But even so, we are not of those who by their own self-imposed limitations of possibility are condemned to find some direct physical contact to account for a similarity of ideas or even of phrasing. Granting, for instance, that there is much resemblance between the teachings of the Dharma of the Buddha and of the Gospel of the Christ, and that the same spirit of love and gentleness pervades them both, still there is no necessity to look for the reason of this resemblance to purely physical transmission. And so for other schools and other teachers; like conditions will produce similar phenomena; like effort and like aspiration will produce similar ideas, similar experience, and similar response. And this we believe to be the case in no general way, but that it is all very definitely ordered from within by the servants of the real guardians of things religious in this world.
We are, then, not compelled to lay so much stress on the question of physical transmission, or to be seeking even to find proof of copying. The human mind in its various degrees is much the same in all climes and ages, and its inner experience has a common ground into which seed may be sown, as it is tilled and cleared of weeds. The good seed comes all from the same granary, and those who sow it pay no attention to the man-made outer distinctions of race and creed.
However difficult, therefore, it may be to prove, from unquestionably historical statements, any direct influence of Indian thought on the conceptions and practices of some of these religious communities and philosophic schools of the Græco-Roman Empire, and although in any particular case similarity of ideas need not necessarily be assigned to direct physical transmission, nevertheless the highest probability, if not the greatest assurance, remains that even prior to the days of Apollonius there was some private knowledge in Greece of the general ideas of the Vedānta and Dharma; while in the case of Apollonius himself, even if we discount nine-tenths of what is related of him, his one idea seems to have been to spread abroad among the religious brotherhoods and institutions of the Empire some portion of the wisdom which he brought back with him from India.
When, then, we find at the end of the first and during the first half of the second century, among such mystic associations as the Hermetic and Gnostic schools, ideas which strongly remind us of the theosophy of the Upaniṣhads or the reasoned ethics of the Suttas, we have always to take into consideration not only the high probability of Apollonius having visited such schools, but also the possibility of his having discoursed at length therein on the Indian wisdom. Not only so, but the memory of his influence may have lingered for long in such circles, for do we not find Plotinus, the coryphæus of Neo-Platonism, as it is called, so enamoured with what he had heard of the wisdom of India at Alexandria, that in 242 he started off with the ill-starred expedition of Gordian to the East in the hope of reaching that land of philosophy? With the failure of the expedition and assassination of the Emperor, however, he had to return, for ever disappointed of his hope.
It is not, however, to be thought that Apollonius set out to make a propaganda of Indian philosophy in the same way that the ordinary missionary sets forth to preach his conception of the Gospel. By no means; Apollonius seems to have endeavoured to help his hearers, whoever they might be, in the way best suited to each of them. He did not begin by telling them that what they believed was utterly false and soul-destroying, and that their eternal welfare depended upon their instantly adopting his own special scheme of salvation; he simply endeavoured to purge and further explain what they already believed and practised. That some strong power supported him in his ceaseless activity, and in his almost world-wide task, is not so difficult of belief; and it is a question of deep interest for those who strive to peer through the mists of appearance, to speculate how that not only a Paul but also an Apollonius was aided and directed in his task from within.
The day, however, has not yet dawned when it will be possible for the general mind in the West to approach the question with such freedom from prejudice, as to bear the thought that, seen from within, not only Paul but also Apollonius may well have been a “disciple of the Lord” in the true sense of the words; and that too although on the surface of things their tasks seem in many ways so dissimilar, and even, to theological preconceptions, entirely antagonistic.
Fortunately, however, even to-day there is an ever-growing number of thinking people who will not only not be shocked by such a belief, but who will receive it with joy as the herald of the dawning of a true sun of righteousness, which will do more to illumine the manifold ways of the religion of our common humanity than all the self-righteousness of any particular body of exclusive religionists.