What Was Epicurus' Position On Skepticism and Dogmatism?

Epicurus taught that not everything can be known, and that we do not have freedom of choice in all things (we have no choice about death) but Epicurus held that some things can be known, and some things are under our control, so Epicurus was strongly against what is termed today both radical Skepticism and hard Determinism.

Epicurus taught that it was important to have confidence in conclusions about matters which are clear. He advised "waiting" to form opinions about things which are not clear. Much of Epicurean doctrine is a reaction against radical skepticism, and in fact one of Epicurus' sayings was "The wise man will teach things that are definite, rather than doubtful musings." (Bailey translation of passage from the Biography of Epicurus by Diogenes Laertius.")

Further examples are: Book Four of Lucretius (Bailey): [469] Again, if any one thinks that nothing is known, he knows not whether that can be known either, since he admits that he knows nothing. Against him then I will refrain from joining issue, who plants himself with his head in the place of his feet. And yet were I to grant that he knows this too, yet I would ask this one question; since he has never before seen any truth in things, whence does he know what is knowing, and not knowing each in turn, what thing has begotten the concept of the true and the false, what thing has proved that the doubtful differs from the certain? [478] You will find that the concept of the true is begotten first from the senses, and that the senses cannot be gainsaid. For something must be found with a greater surety, which can of its own authority refute the false by the true. Diogenes of Oinoanda (Smith): Fragment 5 - Now Aristotle and those who hold the same Peripatetic views as Aristotle say that nothing is scientifically knowable, because things are continually in flux and, on account of the rapidity of the flux, evade our apprehension. We on the other hand acknowledge their flux, but not its being so rapid that the nature of each thing [is] at no time apprehensible by sense-perception. And indeed [in no way would the upholders of] the view under discussion have been able to say (and this is just what they do [maintain] that [at one time] this is [white] and this black, while [at another time] neither this is [white nor] that black, [if] they had not had [previous] knowledge of the nature of both white and black. Thread for discussion of this topic is here.