In C. S. Lewis’ essay “De Audiendis Poetis,” he acknowledges “there are more ways than one of reading old books.”
That anything which takes us outside the poem and leaves us there is regrettable, I fully agree. But we may have to go outside it in order that we may presently come inside it again, better equipped. And what we find inside will always depend a great deal on what we have brought in with us. . . A man who read the literature of the past with no allowance at all for the fact that manners, thought, and sentiments have changed since it was written, would make the maddest work of it.
He poses an important question:
Are we to rest content with ‘putting ourselves back’ into the attitudes of the old author just so far as general education permits, and indeed forces, us to do: or are we to go on and put ourselves back as completely as, with labor and patience, we can?
The answer to this question depends on whether the reader is a historian or a lover of literature. For historians, “there is no question.”
When our aim is knowledge we must go as far as all available means – including the most intense, yet at the same time most sternly disciplined, exercise of our imaginations – can possibly take us. We want to know – therefore, as far as may be, we want to live through for ourselves – the experience of men long dead. What a poem may ‘mean’ to moderns and to them only, however delightful, is from this point of view merely a stain on the lens. We must clean the lens and remove the stain so that the real past can be seen better.
For lovers of literature, “the question admits two answers,” Lewis writes. “You may do which you please.” The contrast he draws between the reader-as-tourist versus the reader-as-traveler is very perceptive.
There are two ways of enjoying a foreign country. One man carries his Englishry abroad with him and brings it home unchanged. Wherever he goes he consorts with the other English tourists. By a good hotel he means one that is like an English hotel. He complains of the bad tea where he might have had excellent coffee. He finds the ‘natives’ quaint and enjoys their quaintness. In his own way he may have a pleasant time; he likes the winter-sports in Switzerland and his flutter at Monte Carlo. In the same way there is a man who carries his modernity with him through all his reading of past literatures and preserves it intact. The highlights in all ancient and medieval poetry are for him the bits that resemble – or can be so read that they seem to resemble – the poetry of his own age.
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But there is another sort of travelling and another sort of reading. You can eat the local food and drink the local wines, you can share the foreign life, you can begin to see the foreign country as it looks, not to the tourist, but to its inhabitants. You can come home modified, thinking and feeling as you did not think and feel before. So with the old literature. You can go beyond the first impression that a poem makes on your modern sensibility. By study of things outside the poem, by comparing it with other poems, by steeping yourself in the vanished period, you can then re-enter the poem with eyes more like those of the natives; now perhaps seeing that the associations you gave to the old words were false, that the real implications were different from what you supposed, that what you thought strange was then ordinary and that what seemed to you ordinary was then strange. In so far as you succeed, you may more and more come to realize that what you enjoyed at the first reading was not really any medieval poem that ever existed but a modern poem made by yourself at a hint from the old words. But that is an extreme case. Sometimes, by luck, your first shot may not have been so wide. Not all things at a given date in the past are equidistant from the present.
Lewis favors the reader-as-traveler.
I am a man as well as a lover of poetry: being human, I am inquisitive, I want to know as well as to enjoy. But even if enjoyment alone were my aim I should still choose this way, for I should hope to be lead by it to newer and fresher enjoyments, things I could never have met in my own period, modes of feeling, flavours, atmospheres, nowhere accessible but by a mental journey into the real past. I have lived nearly sixty years with myself and my own century and am not so enamoured of either as to desire no glimpse of a world beyond them. As the mere tourist’s kind of holiday abroad seems to me rather a waste of Europe – there is more to be got out of it than he gets – so it would seem to me a waste of the past if we were content to see in the literature of every bygone age only the reflexion of our own faces – zum Ekel find’ ich immer nur mich? 
Actually, the two approaches can to some extent be combined. We come to see the old texts with a sort of double vision.
 The full sentence in the Richard Wagner opera of 1870 is spoken by Wotan (reflecting his role as creator deity): “In everything that I create I find forever only myself, ad nauseam”. Lewis quotes only the second half of it “I find forever only myself, ad nauseam”.