"What is the meaning of life?"
This is probably one of the most fundamental questions pertaining to the well-being of mankind. And many of us frequently ask it to ourselves, either consciously or subconsciously, for the sake of avoiding the eternal hellhole of existential crisis.
Yet, finding an answer to such a question requires us to clarify the implication of the word "meaning" in the first place. What does "meaning" really mean, anyways? There could be a wide spectrum of interpretations for sure, but the most obvious one is to regard the word "meaning" as a synonym of "purpose" in the context of biology.
We, as living things, constantly strive to survive and reproduce because it is what biological entities are predisposed to do. This is instinctual, and conscious effort is needed to suppress such a tendency. Since it is the apparent reality of things around us, it is by no means absurd to claim that the meaning of life is to survive and reproduce, and nothing more.
This, of course, feels a bit too shallow and incomplete. As long as we are intellectually flexible enough to let some philosophy dwell in our faculty of metaphysical delight, we retain our desire to muse upon the meaning of not just our biological bodies, but also the universe as a whole. Such an idea, however, does not provide us with a clear guideline for our thought process because it is mostly hypothetical.
The meaning of the world around us, in its entirety, is a rather vague concept to grasp because the very definition of the word "meaning" does not reside in such an abstract context. When people say that something is "meaningful", they typically mean that it is likely to bring some personal advantage to themselves, such as more money, improved health, better relationship, and the like. They might insist that it is supposed to benefit the whole of humanity and not just themselves, yet this is just the same secular notion being applied to a wider scale (i.e. Beneficial to a large number of people instead of just a few). If we are to discuss the meaning of the universe as a whole, outside of even the scope of humanity itself, it is necessary to admit that such a construct is more of a word play than something inducible from our experience.
If we wish to identify the meaning of life from a pragmatic standpoint, therefore, we must avoid groundless speculations and simply begin by investigating what we are supposed to be doing as biological entities. Only after we succeed in making sense of this, we will be able to expand our domain of reason further and manage to define the word "meaning" in a broader context.
The most primary goal we all share as human beings is to survive. As far as our practical definition of causality goes, all other goals are subsidiary to this root goal. For example, we search for food because the act of eating increases our chance of survival, and we seek shelter because the act of staying in a secure area increases our chance of survival. "Search for food" and "Seek shelter" are both goals, yet they are nothing more than subgoals which are aimed to serve their parent goal (i.e. "Survive").
Let us just suppose for now that our purpose is to live as happily as possible. This makes sense, doesn't it? We all want to be happy, and do not want to be miserable. We all want to survive, live, and prosper. This presupposition of value is unquestionable, as long as we do not venture to hypothesize with the very meaning of our existence itself.
The real problem arises, though, when we try to find out a rather specific way to achieve such a goal. There are countless alternative choices of action which may or may not work, depending on who we are. And since every one of us is a unique individual, a method which works for some of us may not work for others. We all have our own ways of living a happy life because we have different talents, preferences, personalities, physical traits, living standards, etc.
So, how to figure out the best way to live? This is probably the most baffling question you can ever ask to yourself, since you are the only one who can figure it out. You are the one who knows about you thoroughly, and thus nobody but yourself can come up with an accurate answer. And its main difficulty lies on the fact that you alone is the only subject you can observe and analyze when it comes to drawing an empirically sound conclusion.
This is indeed frustrating. If you do not know what to do with your life, you won't be able to motivate yourself to do anything in particular. And as long as this state of uncertainty continues, you will always be anxious and depressed.
Fortunately, there is a way to cure at least a significant portion of this problem. Although every one of us is a unique soul and thus requires a unique approach to life, we all share a set of traits which are common to all human beings.
For example, we all know that eating healthy meals, exercising daily, preferring love over hatred, being honest, and being diligent are good for us. These habits are so universally applicable, that one does not even need to question their effectiveness. The key lies on noticing these "common disciplines" and integrating them into your daily routine.
Take the habit of exercise, for instance. No matter what your profession is and what your personal predilections are, it is almost absolutely certain that doing SOME workout on a regular basis will benefit you in some way or another (unless you are suffering from a rare genetic disease, such as one which makes your muscles emit toxic chemicals whenever you use them). This means that, even if you are totally unsure of what you should be doing with your life, you can still be sure of the fact that you should be working out in order to stay fit. The benefit of this habit will not diminish no matter what path your life will happen to follow in the future.
This is the main takeaway of the analysis made so far. If you don't know what to do, at least do something that is worth doing regardless of your future choices. This behavioral guideline will give you a safety net to which you can always fall back whenever circumstances prevent you from making detailed decisions.
Here is the rule of thumb. Focus on doing something which you can manage to do on a regular basis without relying on external factors (e.g. your wealth, your job, place you live, relationships, etc). This will provide you with a "baseline layer of sanity" upon which you can keep moving forward with your life without having to constantly worry about the meaning of what you are doing. This will be the fountain of purpose from which you can drink an endless stream of hope.