trade to power.

i have found trade to be a very important part of the CIV strategy and in my rise to power. while inferior at times to ther civilizations i have made great deals in trading for new technologies for things i have used to thier full potential and do not need at that moment.
in learning of comparative advantage i have found it useful to make things that i can make quickly and trade them for what others may be able to supply better than myself.
trading and receiving new tools has helped me rise to the top of the game and have many allies in the CIV world. but now that i am at the top. trade is not the best for me. what other leaders offer to trade, i already have, and the only way to advance even more is to create my own goods.
manufacturing my own good takes time but is something i must continue inorder to stay ahead of the other civilizations. . .