(adjective) keen, sharp / (adjective) vigorously effective and articulate / (adjective) caustic / (adjective) sharply perceptive; penetrating / (adjective) clear-cut, distinct
Marx actually admired capitalism in some ways, which means that he might have been right about a few things; meanwhile, his trenchant criticisms of it will be treated as the quaintly perceptive observations of an awkward crank
about mainstream publications occasionally "rediscovering" Karl Marx