per·spi·ca·cious 
(pûr′spĭ-kāshəs)
(pûr′spĭ-kāshəs)adj.
Having or showing penetrating mental discernment; clear-sighted. See Synonyms at shrewd.
[From Latin perspicāx, perspicāc-, from perspicere, to look through; see PERSPECTIVE.]
per′spi·cacious·ly adv.
per′spi·cacious·ness n.