all linguists are liars
This book looks like a lot of fun. An excerpt (emphasis added):
"Etymology for its own sake is of little importance, even if it has curiosity value … the chief difficulty is that there can be no 'true' or 'original' meaning since human language stretches back too far." We have to agree with the latter — but the former seems absurd.
It's worth asking at this point why etymology is so seductive. For most people it represents their first (and frequently only) encounter with linguistics. As we know, words are at once completely prosaic — we use them every day, mostly without thinking — and rather mysterious. As a result it's natural to ask where they come from. We weave stories around their origin, both patently false ("lol" and "golf") and more plausible ("decimate" and "educate"). That curiosity shouldn't be dismissed: it's a knocking at the door of linguistics. If they shut it in people's faces, the guardians of knowledge about language risk closing off a route to both enlightenment and wonder. As a result, people seek their wonder elsewhere — in false accounts of how language works.
In any case, it isn't right to see etymology as some poor relation to "proper" linguistics. An attempt to explain why the meanings of words change is an attempt to explain how the mind works, how language works, and how society works. Perhaps this is why it has been deemed out of bounds.