Worn passports

Vladimir Nabokov would probably have produced some nice work in integrated history and philosophy of science:

In art as in science there is no delight without the detail, and it is on details that I have tried to fix the reader’s attention. Let me repeat that unless these are thoroughly understood and remembered, all “general ideas” (so easily acquired, so profitably resold) must necessarily remain but worn passports allowing their bearers short cuts from one area of ignorance to another.

The emphasis is mine.