"What Tarquin the Proud said in his garden with the poppy blooms was understood by the son but not by the messenger.--Hamann,"--Fear and Trembling, Kierkegaard.
"If wisdom were give me under the express condition that it must be kept hidden and not uttered, I should refuse it. No good thing is pleasant to possess, without friends to share it."--Seneca (Letter 6).
Can philosophical writing legitimately call attention to its own limitations? By 'limitation' I do not merely mean (a) the ways in which it its possible philosophical aims are constrained by or even unattainable due to the written form, but also (b) the ways in which it might fall short of other philosophical activities. (Let's leave aside the ways in which it falls short of non-philosophical activities.) For, while (a) can be viewed as a species of self-awareness or truth in advertising, when (b) is true, we might wonder why one is writing at all and not just engaging in those other activities (which by stipulation are better at whatever one is trying to achieve)--at its extreme, then, there might be circumstances where persisting in philosophical writing, however much required (say) for one's sanity, might be an instance of ἀκρασία.
In an otherwise effusive letter (six), Seneca explicitly calls attention to the limitations of his writing when it comes to pursuit of wisdom [sapientia]. At first it seems (echoing Plato's Phaedrus 275a) that he is primarily interested in claiming that "the living voice [viva vox] and the intimacy of a common life will help you more than the written word."[Plus tamen tibi et viva vox et convictus quam oratio proderit.] We might think we're in Derrida's territory. But not all speech is created equally; in context, Seneca rejects learning by attending lectures or even philosophical dialogue. What really facilitates philosophical learning is observing exemplary behavior that can be copied [breve et efficax per exempla]. It's not clear this primarily involves speech at all. Rather, it requires living together with a proper model. Seneca advocates this residential-college approach by comparing it favorably to his own way of teaching, which (among other things) in each letter involves, (i) assigning (authoritative) maxims to be memorized (recall, and here, here) [deinde quia longum iter est per praecepta], and (ii) assigning selected admired texts. In fact, Seneca insists that what, say, Socrates said was far less relevant than his practices (or norms) [plus ex moribus quam ex verbis Socratis traxit] to Plato and Aristotle.*