What do you think will happen if the whole world spoke one language only?

if there is one language for the whole world from the start of life then it would be great and you can reach after 20 years only what you have now in 2016

but if you mean now in this life in this moment one language for the whole world then this moment will be the end of life

i disagree with everyone saying that we can progress faster if we all speak one language , that's totally wrong , we speak different languages because we have different cultures and different experiences that managed to develop a way of communication with each other ( languages ) , and that means that we think and act diffrently , so we have progress in many fields at the same time , if we all speak one language it means we all think and act alike and that won't help progressing at all .

Everything in life has positive sides and negative. One language for all that can develop science, facilitate communication between people. I think one language accelerate technical process. But at the same time one language integrate culture. That means our cultural heritage will be very poor. Different languages enrich World culture

Well it seems good and easy to speak one language since it will enable all people to understand eachother quickly, but I suppose that it will be somehow bad or rather dangerous because it might lead us to forget our thoughts ,habits, traditions, and culture which are usually correlated with language.