A follower, or admirer, or even someone merely interested in the Stoic philosophy should consider its application in the case of the more visceral of the emotions. I think this is required for an honest appraisal of the effectiveness of stoic practice and of the validity or appropriateness of the philosophy itself.
Of course "visceral" may be deemed to apply to all the emotions to the extent they're not founded on reason. However, for purposes of this post, I use "visceral" to refer to those emotions which are peculiarly intense; irrational, certainly, as are other emotions, but also having characteristics which are significantly physical or result in physical symptoms, as it were.
I think one of these emotions is fear, particularly where fear manifests itself in such conditions as cold sweats, nausea or an "icy" feeling in the stomach, and even (I suppose it must be said) trembling. In my case and apparently in many other cases, such a fear is the fear of heights. Not that I'm overwhelmed by a beautiful vista enjoyed from a secure location high on a hill or mountain; certain of my encounters with high places have actually been enjoyable, particularly when I'm accompanied in my encounter by an alcoholic beverage of my choice. But in some circumstances, my fear of heights can be paralyzing.
I went zip lining recently, in Jamaica on what's called Mystic Mountain. This interesting pastime is not one I've pursued in the past, and it wouldn't be accurate to say I pursued it in this case. Rather, I made a decision to "zip" despite the fact that I feared doing so. I wasn't surprised to find that I felt fear while doing so as well. I also felt fear while enduring the agonizing ride up to the starting point of the "zip" on the very high, disturbingly slow, ski-lift or ski-lift equivalent which is the only means of transport available to prospective "zippers." Slowly making a steep ascent sitting on a kind of thin bench with nothing to hold onto but an appallingly small metal bar as one dangles in the air is, for me, a terrifying experience.
Well, I managed to endure the terror of the ascent and zip lining as well, and am in an odd way pleased at my endurance. Whether I will ever zip line again is an open question. But there is something good about overcoming one's fear; something satisfying in any case.
Now in enduring these experiences I made an effort to apply stoic practice. For example, I reminded myself that whether the ski-lift would function properly, and whether the lines on which I zipped would or would not break, were things quite beyond my control; I reminded myself that Epictetus noted that how and when we would die, as die we will, are also beyond our control; that death is not a thing to fear; that height should no more be a source of fear than any other characteristic of our necessary interaction with the rest of the world, with nature.
It's possible that these considerations contributed to my endurance. But the fear most certainly was present as were its "symptoms" although those symptoms were not severe enough to render me helpless or a gibbering wreck, and I think that but for white knuckles and a notable rigidity, and a demeanor which would have been, at best, grim, I did not appear significantly distressed.
It may be that I haven't devoted enough time and effort to the kind of "spiritual exercises" one sees in the thoughts and sayings of Epictetus and Marcus Aurelius, but I speculate that my fear of heights will never be eradicated by being a Stoic, or at least attempting to be a Stoic. I think it's fair to say, however, that stoic practice has eradicated or at least rendered minimal my emotional reactions in other cases, i.e. in those cases which don't involve my fear of heights, but which stoic practice has established to my satisfaction should not be allowed to disturb me.
Perhaps the fear of heights and similar fears must be distinguished from other feelings. Perhaps such fears are based on considerations or conditions which are, so to speak, immune from Stoic philosophy. I'm not certain of this, though, as Epictetus at least evidently said with some frequency that it should be a matter of indifference whether, e,g., the emperor kills us or incarcerates us, and it would appear the fear of death is for many of us the equivalent of my fear of heights. So one may infer that to Epictetus the ideal Stoic, the Stoic Sage, would in some manner have extinguished such fears and other "visceral" emotions of feelings.
My thought at this time is that such fear cannot be extinguished; however, it's possible it can be restricted, limited--endured. To the extent the Stoic philosophy may promote such endurance, however, it is valuable even when applied to those fears and emotions we feel so powerfully "in our guts."