There are two reasons for this inability:

1. There is no connection between function (functioning, functionality) and meaning (meaninglessness, meaningfulness).
2. There are different interpretations of the word "Meaning" and, yet, people use them interchangeably, obscuring the dialogue.

People often confuse Meaning and Function. When asked what is the meaning of their life they respond by using function-laden phrases. They say: "This activity lends taste (=one interpretation of meaning) to my life", or: "My role in this world is this and, once finished, I will be able to rest in pace, to die". They attach different magnitudes of meaningfulness to various human activities.

Two things are evident:

1. That people use the word "Meaning" not in its philosophically rigorous form. What they mean is really the satisfaction, even the happiness that comes with successful functioning. They want to continue to live when they are flooded by these emotions. They confuse this motivation to live on with the meaning of life. Put differently, they confuse the "why" with the "what for". The philosophical assumption that life has a meaning is a teleological one. Life - regarded linearly as a "progress bar" - proceeds towards something, a final horizon, an aim. But people relate only to what "makes them tick", the pleasure that they derive from being more or less successful in what they set out to do.
2. Either the philosophers are wrong in that they do not distinguish between human activities (from the point of view of their meaningfulness) or people are wrong in that they do. This apparent conflict can be resolved by observing that people and philosophers use different interpretations of the word "Meaning".

To reconcile these antithetical interpretations, it is best to consider three examples:

Assuming there were a religious man who established a new church of which only he was a member.

Would we have said that his life and actions are meaningful?

Probably not.

This seems to imply that quantity somehow bestows meaning. In other words, that meaning is an emergent phenomenon (epiphenomenon). Another right conclusion would be that meaning depends on the context. In the absence of worshippers, even the best run, well-organized, and worthy church might look meaningless. The worshippers - who are part of the church - also provide the context.

This is unfamiliar territory. We are used to associate context with externality. We do not think that our organs provide us with context, for instance (unless we are afflicted by certain mental disturbances). The apparent contradiction is easily resolved: to provide context, the provider of the context provider must be either external - or with the inherent, independent capacity to be so.

The churchgoers do constitute the church - but they are not defined by it, they are external to it and they are not dependent on it. This externality - whether as a trait of the providers of context, or as a feature of an emergent phenomenon - is all-important. The very meaning of the system is derived from it.

A few more examples to support this approach:

Imagine a national hero without a nation, an actor without an audience, and an author without (present or future) readers. Does their work have any meaning? Not really. The external perspective again proves all-important.

There is an added caveat, an added dimension here: time. To deny a work of art any meaning, we must know with total assurance that it will never be seen by anyone. Since this is an impossibility (unless it is to be destroyed) - a work of art has undeniable, intrinsic meaning, a result of the mere potential to be seen by someone, sometime, somewhere. This potential of a " single gaze" is sufficient to endow the work of art with meaning.

To a large extent, the heroes of history, its main characters, are actors with a stage and audience larger than usual. The only difference might be that future audiences often alter the magnitude of their "art": it is either diminished or magnified in the eyes of history.

The third example - originally brought up by Douglas Hofstadter in his magnificent opus "Godel, Escher, Bach - An Eternal Golden Braid" - is genetic material (DNA). Without the right "context" (amino acids) - it has no "meaning" (it does not lead to the production of proteins, the building blocks of the organism encoded in the DNA). To illustrate his point, the author sends DNA on a trip to outer space, where aliens would find it impossible to decipher it (=to understand its meaning).

By now it would seem clear that for a human activity, institution or idea to be meaningful, a context is needed. Whether we can say the same about things natural remains to be seen. Being humans, we tend to assume a privileged status. As in certain metaphysical interpretations of classical quantum mechanics, the observer actively participates in the determination of the world. There would be no meaning if there were no intelligent observers - even if the requirement of context was satisfied (part of the "anthropic principle").