It's a question asked often, especially by classicists who despair for self-justification. Well, here's one humble response from 1964:
In the days when they formed the basis of a common culture for all educated Europeans, classical studies, together with the Bible, provided an outline of nearly all that was known or believed about world history and a background to the history of modern times and of the Middle Ages. Today, to speak of 'two cultures' is to understate: the Arts themselves are fragmented. Modern history, reaching back only a few generations, lacks depth; mediaeval history both begins and leaves off in the middle of the story; classical studies have become too narrowly philological.The author was A.R. Burn (Proceedings of the Classical Association LXI, 1964, 27–28), most widely known by students as the author of The Penguin (formerly Pelican) History of Greece, first published under the title A Traveler's History of Greece a year after this talk was given. (I suppose this could be another's summary of his talk — it's given in a list of 'reports' from the General Meeting — but I suspect that it was his abstract.
Our civilization needs classical scholars, as it needs sinologists, not only to train their successors but primarily for the sake of the wider public. There is a wide and spontaneous demand for knowledge about the origins and development of our civilization, manifested both in sales of books and in willingness to spend money on travel in the Near East. We could, and ought to, be satisfying this demand.
At first sight the length of time — some 5,000 years since the first recorded dynasties — sounds overwhelming. But the appropriate measure of time is the human generation: the number of perhaps 200 since the beginning of recorded history and less than 100 since Homer is a modest one.
We can here learn from American colleges, which have long taught world history or 'western civilization', not least that the study of Greek and Roman history can play a great part by bringing out the extraordinary resemblances between some of the great processes villain that history and the history of the Christian West. The re-growth of a culture, under stimulation from the East after the collapse of a previous civilization; the expansion to a more spacious world in the West and its effects on the old world's economy and society; the bold astronomical and geological speculations; the class-struggles and revolutions; the disastrous failure to transcend inter-state rivalries and wars — all these things have reminded scholars of the history of their own age. At the same time Greek thought and art have in some ways more resemblance to those of mediaeval Christendom than to modern trends.
Even an outline knowledge of Greek and Roman history could be of immense value to specialists in modern fields. We should be devoting our best efforts to trying to convince our colleagues of this, and should be training our pupils to restore some unity to our culture, as well as training their successors.
Still sound sensible enough to me.