But with respect to placing a city in the neighbourhood of the sea, there are some who have many doubts whether it is serviceable or hurtful to a well-regulated state; for they say, that the resort of persons brought up under a different system of government is disserviceable to the state, as well by impeding the laws as by their numbers; for a multitude of merchants must necessarily arise from their trafficking backward and forward upon the seas, which will hinder the well-governing of the city: but if this inconvenience should not arise, it is evident that it is better, both on account of safety and also for the easier acquisition of the necessaries of life, that both the city and the country should be near the sea; for it is necessary that those who are to sustain the attack of the enemy should be ready with their assistance both by land and by sea, and to oppose any inroad, both ways if possible but if not, at least where they are most powerful, which they may do while they possess both. A maritime situation is also useful for receiving from others what your own country will not produce, and exporting those necessaries of your own growth which are more than you have occasion for; but a city ought to traffic to supply its own wants, and not the wants of others; for those who themselves furnish an open market for every one, do it for the sake of gain; which it is not proper for a well-established state to do, neither should they encourage such a commerce. Now, as we see that many places and cities have docks and harbours lying very convenient for the city, while those who frequent them have no communication with the citadel, and yet they are not too far off, but are surrounded by walls and such-like fortifications, it is evident, that if any good arises from such an intercourse the city will receive it, but if anything hurtful, it will be easy to restrain it by a law declaring and deputing whom the state will allow to have an intercourse with each other, and whom not. As to a naval power, it is by no means doubtful that it is necessary to have one to a certain degree; and this not only for the sake of the [1327b] city itself, but also because it may be necessary to appear formidable to some of the neighbouring states, or to be able to assist them as well by sea as by land; but to know how great that force should be, the health of the state should be inquired into, and if that appears vigorous and enables her to take the lead of other communities, it is necessary that her force should correspond with her actions. As for that multitude of people which a maritime power creates, they are by no means necessary to a state, nor ought they to make a part of the citizens; for the mariners and infantry, who have the command, are freemen, and upon these depends a naval engagement: but when there are many servants and husbandmen, there they will always have a number of sailors, as we now see happens to some states, as in Heraclea, where they man many triremes, though the extent of their city is much inferior to some others. And thus we determine concerning the country, the port, the city, the sea, and a maritime power: as to the number of the citizens, what that ought to be we have already said.