If you want to read Confucius in the original language, you need to know Classical Chinese. If you want to know much of the later two and a half millennia of Chinese philosophy, you need to know Literary Chinese. (Classical Chinese is, roughly, like Classical Latin. Literary Chinese is kind of like Medieval Latin. Contemporary Mandarin Chinese is like Italian.) Sometimes I am confronted with comments of the form, “Surely, So-and-so reads Classical Chinese.” If the comment needs to be made, the answer is generally “Not really…and don’t call me ‘Shirley.’” (Sorry. I guess that joke only works if you say it out loud.)
More seriously, there is a long-running debate in language pedagogy of what counts as “being able to speak language X.” Everyone agrees that there are levels of competence, with one end being absolute lack of any knowledge and the other being fluency equal to an articulate native speaker. Beyond that, the lines are hard to draw. For modern Mandarin, the gold standard is now the Hanyu Shuiping Kaoshi (HSK), administered by the China National Office for Teaching Chinese as a Foreign Language, an official People’s Republic government organ. The HSK certifies one in speaking, aural comprehension, written comprehension and even writing at the beginning, intermediate and advanced levels. Performance on each level is certified as no rank (failing), “acceptable,” and “honors.” I’ve never taken the exam, but I suspect that I would probably be intermediate acceptable. Do I “speak Mandarin Chinese”? I think so. I can order in restaurants, give directions to a cab driver, introduce myself to people and exchange pleasantries, and even stumble my way through a public talk, although I dread it and often have to turn to a bilingual colleague for help when I get stuck. (怎麼說 ‘Categorical Imperative’ 用中文?)
There is nothing comparable to the HSK for Classical or Literary Chinese. However, here is a rough standard I would support. Paul Rouzer’s A New Practical Primer of Literary Chinese (Harvard East Asian Monographs, 2007) is a textbook used by many good schools. (I’m using it in my Literary Chinese course next year.) One of the nice things about Rouzer’s book is that all the texts, beginning with Lesson 1, are authentic Classical or Literary Chinese texts. I would say that if you can read the sample texts in Unit 1 (Lessons 1-10) — without using Rouzer’s lexical and grammatical notes — then you have functional ability in Classical or Literary Chinese. (The constructions are all basic enough that anyone should be able to read them, whether they focus on Classical or Literary Chinese texts.) Okay, tell you what. You can use a dictionary a maximum of 10 times to look up any characters you happen not to know. (I dumbed out on 縛 in Lesson 10, so I have to cut everyone else some slack.) But if you can’t read those introductory texts fairly easily, even with a limited-use crutch — well, then you don’t really “read Classical/Literary Chinese.”