Which one is more difficult to learn, English or Chinese?

Of course, they are two greatest languages in the world. One exerts the most powerful synchronic influence over the face of the Planet. The other, on the contrary, might be the strongest diachronic language that has been weaving together the history of a single largest country in population and later its much smaller neighbors since its first emperor froze the writing system of the language for the first time when the country proper came into being in A.D. 221.

Which one is more difficult for a foreign learner to learn to speak and write? The Chinese. Someone has commented that one needs three months to learn good English, three years to master French and at least thirty years to be proficient in German. As I see it, he has to double his efforts he has put in tackling German to speak and write good Chinese and those who have mastered Chinese in 60 years much better than an average Chinese person has in 20 years must be geniuses.

This is definitely of no overestimation. For one thing, most of native Chinese speakers (I'm one of them) find it hard to write decent Chinese because they have long been isolated from the traditionally accepted and correct way of writing and do not know how they should write while an averagely educated native English speaker is taught a set of clear rules to follow in writing, partly owing to the long established convention of "free speech" and "speaking up for oneself". This poses a serious challenge to foreign learners of Chinese-they have to find decently and elegantly written Chinese writings to copy. Older writings, more often than not, sound too old-fashioned, especially those written before 1949, and even 1978. It seems to me that the correct, smooth and natural tradition of writing Chinese was broken somewhere (during the Great Cultural Revolution?) so that its modern speakers are at a loss to know how to write their language. For example, many news reports, government documents and corporate files are badly written, if not most of them. Experts, or rather those of at least writing elegant Chinese, are hard to come by these days.

For another, for the Chinese language, its grammar rules appear to be overshadowed by conventions and exceptions. Though there are grammar rules to follow, the too many conventions and exceptions make those rules almost meaningless sometimes. As far as I know, no complete and generally agreed Chinese grammar system has been established out of the language and the current system, if it is one, is believed to be a poor relation of its Western counterparts.