So long as truth is held as valuable, then honesty will be highly regarded.

Integrity will be guarded as trade routes, and lies hunted as thieves.

When all you have is someone's word to base decisions on, the reliability of his word, which usually means the truth of it, is a treasure and if it is missing... how poor indeed is that man.

Because humans are social creatures which rely on the success of the group to survive, lying is typically an act that hurts the good of the group and is thus seen as wrong because it would hurt the group and by proxy it would hurt you. However I say that lying isnt wrong if it benefits you, for instance monkeys have been observed to lie. Let me explain; monkeys are social creatures and have certain calls to signal danger so they can retreat to the trees while gathering food if there is a threat to them, now the dominant monkeys will often take and consume the food that weaker and more submissive monkeys found, however some of the weaker monkeys will use the danger call when they find food so they other monkeys flee while the weaker monkey eats the food it found. So you see lying is only considered wrong or "immoral" when it is perceived as detrimental to your individual success. We perceive it as wrong because it hurts the good of the group which in turn hurts your success.