Time: The most precious resource
The passage of time is concept that I've spent a great deal of effort trying to wrap my mind around. It is especially problematic because while time itself is a constant, it's perception in our minds is continuously in flux. It's worthwhile, if you're able to, to try and slow time down as much as possible and try to get the most out of each moment. Time itself is far more valuable than money, fame, possessions, etc. – probably the most important real or abstract resource there is. When I'm running my tech PR agency, I'm forever running out of it, and it sucks.
Value itself can be measured in time, even more so than money, for if you can get people to devote time to your cause, this can in many cases demonstrate that they are even more interested in helping you/your cause than those who simply give money. The people who say 'time is money' are right to a degree, but I'll go a step further and say that 'time is more precious than money." You can always get more money – but there is no way to gain extra time; only extend the experience and perception of it.
Time is so important because we only have X amount, where X equals moments in existence. You really can't stretch it much further than what our physical bodies were designed to handle (this does vary slightly based on genetics), but I would say more than a raw number, how you spend those moments (whatever you most intimately enjoy doing) make up the purpose and function of that time. Looking back on life with regret is only a waste of time if you didn't learn and grow from those experiences, and I do not believe you are ever wasting time if you are learning, growing and broadening your understanding of yourself, your interests and humanity itself.
Who you surround yourself with and what you do during the X amount of moments on earth speaks volumes for what exactly you represent, and even if you think or speak a certain way, how you spend your time will almost always reflect your true persona. People spend a great deal of time simply thinking about ways they can change their lives, and how "next year of my life" will be better – but this isn't true, and is an unfortunate squandering of time. Your life will never change and you won't all of a sudden start accomplishing your goals – unless of course you make a change right now, at this moment in time. Simply thinking about making a change will almost always result in no change.
Now is a powerful word, something many people have a hard time grasping. Everyone wants to make changes to their lives, but I've discovered that only those who act decisively and have the self-control to put something into action at will are the most successful human beings, and able to alter the course of their lives. We should all freely be enjoying our time while also respecting it, and using our time to mold ourselves like clay into an ideal self-image of what we want to be. This should be one of our most treasured goals in life, and I think we should all be using our time in this manner.