Altruism would suffice but, how to acheive it? Breeding, education, having one universal language instead of many?
Which language is the easiest to learn and the most efficient? I can’t vote for English because well, This forum speaks of how complicated and innefficient it is. 
Honest communication is impossible.
I dont think altuism must require some sort of knowledge-driven set-up. But I guess language would be some sort of education, but is langauge alone any kind of truth if it does not move beyond practical utility?
I think a single language would, like a single world-state, lose diversity and therefore prove dangerous. But it´s great to have a world-wide language, notwithstanding its pretty inconsistent grammar and spelling.
I think it is one solution and it certainly sums it up.
Altruism generally can’t happen, It’s an irrational ideal, lies are detrimental most of the time and truth the opposite. The examples given trying to point out lying can be beneficial show are quite ridiculous.
It´s funny how the Greeks saw knowledge and virtue/the good life as pretty much synonymous. Yet nowadays, people like Foucault equate it with power, often of a tyrannical sort. I guess it´s what you do with it that counts, implying perhaps that knowledge is not intrinsically good or bad. Hence my view that rationality and irrationality have no direct link to altruism and egoism. Moreover, isn´t it the passions which ultimately stir one to act? I´d imagine a completely egoistic society would look very different.
There´s a classic case where lying is clearly beneficial:
An innocent person flees an axe-wielding maniac, who asks you where they ran… should you really point the way?
Can you honestly say utter truthfulness would make for very content relations?
Rationality is dangerous. Nothing is rational. But the pursuit of something pointless and well meaning is a greater pursuit than the pusuit for something for the common bad do you think?
Lies are just mis-shapen truths, there is no such thing really as a “non truth”, a lie is just a partial truth.