Fashions of dress, equipage and decorous usage, e.g., run with some uniformity throughout these modern nations, and indeed with some degree of prescriptive force.

There is, of course, nothing mandatory, in the simpler sense, about all this; nor is the degree of conformity extreme or uniform throughout.

But it is a ready-made generalisation that only those communities are incorporated in this cosmopolitan coalescence of usage that are moved by their own incitement, and only so far as they have an effectually felt need of conformity in these premises.

It is true, a dispassionate outsider, if such there be, would perhaps be struck by the degree of such painstaking conformity to canons of conduct which it frequently must cost serious effort even to ascertain in such detail as the case calls for.
Doubtless, or at least presumably, conformity under the jurisdiction of the fashions, and in related provinces of decorum, is obligatory in a degree that need not be looked for throughout the scheme of use and wont at large, even under the advisedly established non-interference of the authorities.

Still, on a point on which the evidence hitherto is extremely scant it is the part of discretion to hold no settled opinion.
A more promising line of suggestion is probably that afforded by the current degree of contact and consistency among the modern nations in respect of science and scholarship, as also in the aesthetic or the industrial arts.