I was tempted to choose A waste of time but, considering that some people here seem to find frequency dictionaries useful, I chose Overrated instead.
In my opinion the fundamental problem with all frequency dictionaries and wordlists is the belief that the word – in its various incarnations – is the fundamental unit of a language. So, learning a language consists basically of learning a bunch of words.
This is clearly stated in the foreword of the Spanish Frequency Dictionary Advanced Vocabulary (5001 – 7500 Most Common Spanish Words)
« …The Collins Spanish Dictionary (August 2016 edition) lists over 310,000 words in current use, while you will only need to know 1.62% (5000 words) to achieve 95% and 89% fluency in speaking and writing. Knowing the most common 10,000 words, or just 3.25%, will net you 98% fluency in spoken language and 95% fluency in written texts. »
https://www.amazon.ca/-/fr/MostUsedWords/dp/9492637235/ref=cm_cr_arp_d_bdcrb_top?ie=UTF8&asin=9492637235&revisionId=&format=4&depth=1I believe that these figures are totally misleading. The use of the word fluency instead of proficiency is very irritating to me. But more importantly, there is no definition of what it means to know a word.
What should be emphasized here is that we are really talking about knowing how to use the words appropriately in a multitude of contexts.
In reality, the isolated word does not mean much. Any good dictionary will give example sentences that illustrate the use(s) of a word. The fundamental unit of a language is something along the lines of a phrase.
This is readily apparent when we look at idiomatic expressions that Iversen discusses earlier. This is a whole world of complexity in itself that frequency dictionaries are not designed to handle and for which we have idiom dictionaries.
I thus believe that trying to quantify vocabulary size is a fool’s errand. Proficiency is not determined by a given number of words but by the ability to use the words in your command. Vocabulary size is determined by the topic that one is speaking or writing about and will expand accordingly with exposure. This is exactly what happens in our native languages when we spontaneously acquire new words as we acquire new knowledge.
So the fundamental issue for vocabulary acquisition is exposure. Reading one good book will expose you to all the fundamentals of the language you need to know. Right now I am finishing the Ken Follet's 474-page novel
Whiteout. For the English-learner this one book contains all the fundamentals of written and spoken English. Of course, there are other types of English, such as academic and technical language, that are not much present in this work. Obviously, one should read a varied range of material to get exposure to different varieties of the language, but the point I want to make here is that just one good book can give the reader a very complete exposure to the language without having to bother with trying to learn the most frequent words by themselves.
Edit: correct minor typos