History of the Peloponnesian War
Thucydides
Thucydides, Vol. 1-4. Smith, Charles Foster, translator. London and Cambridge, MA: Heinemann and Harvard University Press, 1919-1923.
For as regards the first, it is a difficult matter even in time of peace to construct here a city that will be a match for ours, to say nothing of doing this in a hostile country and at a time when we have fortifications quite as strong to oppose them.
But suppose they do establish a fort; although they might injure a part of our territory by making raids and receiving our deserters, yet that will not be sufficient to prevent us from sailing to their land and building forts there, or making reprisals with our fleet, wherein our strength lies.
For we have gained more experience of operations on land from our career on the sea than they of naval operations from their career on land.
As for their acquiring the art of seamanship, that is an advantage they will not easily secure;
for even you, who began practising it immediately after the Persian war, have not yet brought it to perfection. How then could men do anything worth mention who are tillers of the soil and not seamen, especially since they will not even be permitted to practise, because we shall always be lying in wait for them with a large fleet?
For if they had to cope with only a small fleet lying in wait, they might perhaps risk an engagement, in their ignorance getting courage from their mere numbers; but if their way is blocked by a large fleet, they will remain inactive, their skill will deteriorate through lack of practice, and that in itself will make them more timid.