open sense

Can you give us the whole sentence?

Unlike any other place on the planet. LA shows us the potential of development once the Third World mentality merges with an open sense of possibility ,a culture of organization, a Western conception of time.

I have no idea of the meanings of the words in red.

open sense of possibility - one has the ability to see vast prospects lie before one, consequently one can explore every avenue, leave no avenue unexplored ->a culture of oragnization <- to know how to use the open sense of possibility; = organizing culture;

mentality = mental constitution/make up, turn/cast/attitude of mind; mind, thought.