so to speak= this is one way to say it /in a manner of speaking In a manner of speaking, we have to pull down the ' barriers' of poverty.

In English there are words of expressions one could call “conversation fillers” because they fill in the space or the time between words. These expressions usually have no meaning and do not add anything to the communication. They are often used by people who are not good public speakers, by those who are a little nervous or by those who are searching for something else to say. “So to speak” is one of these expressions. Others are “you know,” “um,” “eh,” “like.” It’s a little annoying to listen to someone who uses such fillers frequently. Our local TV weather reporter uses “I would say” in such a manner and I’ve heard her throw it into her reporting four times in one minute. http://voices.yahoo.com/conversation-fillers-4638537.html?cat=4

Poverty doesn't have "physical" barriers, so, if one says "pull down the barriers of poverty", it is a figurative way of speaking, that is why "so to speak" is used in this case. The sentence could also be written this way: Speaking in a figurative sense, we have to pull down the barriers of poverty.

Wow good luck with that question. But I will come back and check on other people's answers, because that expression is used all the time. But I can not think of a real definition of what it really means. All it basically is, is extra words that people say, just to say they are telling you something. And ofcourse you already know they are telling you something, because they are in the process of telling you something. Like the sentence that you have above, all the expression is saying is : the person is speaking to you about poverty, but you already know they're speaking to you about poverty, because they're telling you at the same time that they're saying that expression. And believe me, I hear that expression all the time from people, but to me, it has an empty meaning. Maybe it's just extra words that people say in a sentence just to exercise their jaw muscles more? heehee... I don't know? Let me give you another example sentence : Why do so many people use that expression, so to speak, of that expression?... I hope you get some good answers, because I'm very curious of the actual reason/meaning for that expression. Sorry I couldn't help :( But please don't take down your question too soon, if it get's a good answer, so maybe I can understand a better meaning of it too :) Thank you