Nevertheless we cannot but observe a distinct intellectual advance among the Arabs of the period we are now considering. This is specially marked in the efflorescence of poetry. It is of a purely national character and differs wholly from the poetry of northern Semitic races both in structure and substance. We know it only in its fully developed form, the oldest poems which have come down to us in tolerable preservation are of precisely the same character as the later ones, but even they only date back to the first half of the sixth century at farthest. All Arabic poetry is rhymed, and rhyme predominates even in certain solemn modes of speech not subject to strict metrical rule, such as the apothegms of soothsayers. Now, seeing that this form of poetry, up to that time everywhere unknown, springs into prominence in Latin and Greek poems of a popular and devotional character after the fourth century, we are led to conjecture that there may be a connection of some sort with occidental poetry in the employment of this artistic method, which may very well have come into use among the Arabs about the same time. The point of common origin might be Palestine or Syria. Rhymed prose was probably the original form. The whole matter is, however, beyond proof. The acceptance of this conjecture would not impair the originality of Arabic poetry. Among its great merits is the extremely fine feeling for rhythm which the entirely illiterate Arab authors of these poems and of the rhapsodies which were handed down orally display, by the careful observance of metres which carry out the principle of quantity far more strictly than those of Greek and Latin poetry. In substance these poems generally turn upon the ordinary subjects and interests of Bedouin life, though frequently idealising them; and loftier thoughts are not seldom conspicuous. Some famous poets who took long journeys, sometimes living among Christian surroundings at the courts of Arab vassal kings, sometimes going as far as to Yemen, prepared the way for Islam by disseminating ideas tinged with Christian thought. The spirit that animates the noble tales of Arab heroes and worthies which originated at this time points to an advance in culture. One singular institution appears to have had very advantageous results; during certain months all heathen Arabs observed a truce of God, in which arms were laid aside and no blood was shed. During this period friends and foes met together at certain times and places, originally, no doubt, to celebrate religious rites. By degrees, however, the latter receded into the background; negotiations were carried on, treaties concluded, the poets found an audience, merriment and brisk traffic were the order of the day. Even in the festival at Mecca, which retained more of its religious character, the varied programme ran its round.[16] RELIGION OF THE ANCIENT ARABS