Is perception real or is reality is defined in terms of perception? This definitely reduces to the chicken-egg problem. But many deep philosophical questions are reduced to this problem. This problem is Ph-Complete (Philosophically Complete) that is if this problem is solved then any philosophical question can be answered. Now since we donot have a solution for this problem we have to focus our energies on approximations based on assumptions which is called practicality. We have to live with it. Even computer scientists cannot avoid such situations:) Lookup NP-Completeness.
Now the question I started with, is important in life to do something meanigful and worthy. Since we donot know what is the true definition of reality or perception what we can do is be efficient in balancing both. Dynamic balance of perception and reality is important in life. Live in the present. If you live too much on the past you are giving to much weight to perceptual reality and if you worry too much about future then you are having un-realistic perception. You can see a post that talks about unrealistic perception. Importance of balance in life comes from age-old wisdom. When you don't have any opinion or neither realistic perception nor perceptual reality it does not mean you are balanced - it just means you are ignorant of things around you. One has to constantly progress, do things but maintain balance. Only then balance is meanigful.
Importance of dynamic balance is hinted by Nature in it's every aspect: Earth is round, circle is a unique geometric object, there are cycles in seasons, most cosmic paths are closed even if very large. The heavenly bodies keep moving but are in equilibrium nurturing life and energy.
How can we try to achieve this balance? Science and Art are the answers. Science tries to give us realistic perception and Art contributes by stressing perceptual reality. Thus they both are, equally importantly, helping humanity. Morals, emotions etc. are like software for the hardware built by more objective Science.