this type, together with the adjective derived from it, corresponds to the verbal noun and adjective of the first type. Its verbal noun follows the fa‘lala pattern, as in waswasa and zalzala, or the fi‘lān pattern, as in zilzāl.

Of these two verbal-noun patterns, fi‘lān is more consistent with analogy and more appropriate to both types of fa‘lala, for two reasons.

First, fa‘lala resembles af‘ala in its number of letters, with a fatḥa on the first, third, and fourth letters and a sukūn on the second. Accordingly, if‘āl was made the verbal noun of af‘ala, and fi‘lāl the verbal noun of fa‘lala, so that the two verbal nouns would resemble one another just as the two verbs do. Thus, fi‘lāl is more appropriate to this verbal pattern than fa‘lala.

Second, the basic principle is that a verbal noun should differ in pattern from its verb. The difference between fi‘lāl and fa‘lala is greater than that between the verbal-noun pattern fa‘lala and its verb. Thus, fi‘lāl has a stronger claim to serve as the verbal noun than fa‘lala; alternatively, the two are equally regular, although fa‘lala is more prevalent and frequent in actual usage. This is the basic rule.

Nevertheless, verbal nouns of this reduplicated pattern have also been used with a as their first vowel.

Thus, they say: waswasa al-shaytānu waswāsan (“Satan whispered”); wa‘wa‘a al-kalbu wa‘wā‘an, when a dog howls; and ‘az‘aza al-sahmu «1» ‘az‘āzan (“the arrow quivered and swerved”). The form consistent with analogy is fi‘lāl, with i as its first vowel, or fa‘lala. The form with a as its first vowel is rare. This is because the non-reduplicated quadriliteral is the basic form from which the reduplicated form derives. Yet the verbal noun of the non-reduplicated form, despite its being the basic form, occurs only as fa‘lala or fi‘lāl, with i as the first vowel. It is therefore fitting that the reduplicated quadriliteral, being derivative, should likewise have no other verbal-noun forms. A derivative does not depart from its basic form but follows its example. This requires that its verbal noun should not follow the fa‘lāl pattern, with a as its first vowel. If an exceptional instance occurs, it is retained as attested, but no further forms are coined by analogy with it.

They say: Furthermore, fa‘lāl, with a as its first vowel, frequently occurs as an adjective formed from reduplicated fa‘lala, serving as its counterpart to fa‘‘āl in triliteral verbs, since the two share the same metrical shape.

This entails that fa‘lāl should have no role as a verbal noun, just as fa‘‘āl does not