It seems that the Gemara is simply telling us of a physical effect, perhaps relating to the vibrations of the air caused by speech. Wine, which is a liquid which is left to rest perfectly still in order that the dregs do not become mixed with the wine, is perhaps adversely affected by such vibrations, while Ketores, which is made through *grinding*, is beneficially affected by them.

Aside from the physical affects, there might be allegorical allusions in the Gemara's statement as well. See for instance, what we brought in Yosef Da'as in the name of Rav Kook, Z'L.

Another allegorical allusion might be related to the fact that wine represents sin that is brought about by involvement in the physical pleasures (since it involves imbibing an intoxicating potion into the body), see Sanhedrin 70a. Ketores, on the other hand, is a source of the metaphysical pleasures of the soul (since the sense of smell involves deriving pleasure from something that cannot be seen; the Gemara in Berachos 25a, 43a, cites the Pasuk "Kol ha'*Neshamah* Tehalel Kah" to describe the pleasures of smell).

We find in Chulin 89b that a person should use his mouth only for the study of Torah; any use for non-Torah discussion is detrimental. Hence, speech is damaging to "wine" (i.e. if used for physical purposes, it can only cause damage), but it is helpful for "Ketores," i.e. the metaphysical.

Be well, Mordecai Kornfeld