Now ask yourself the same questions about other music examples. You can extend that search for intuitive understanding, feeling and experiencing of a tiny particle of a musical piece to memories and even further to the deepest secret and unknown regions of yourself. . Because you are an absolute unique human being - like everybody else. Still - a funeral march means mourning the death of someone close. We all know that general feeling as well as we all know the joy of the power and brightness of a spring day.
Music is able to express all of that and infinitely more.
The more specific your personal experience about that becomes, the more it differs on a material level. The same is true for the composer and his piece. Although a composition is based on basic materials the unique personality of the composer expresses itself in the most refined, subtle and personal way. The amazing thing is, that the composer had a feeling for one particular Idea and at the same time an idea for that particular feeling for himself and a certain sounding materialization is what he found to express it. It appeals to our archetypical level of experiencing reality, the understanding and feeling is rooted in us, in what we are regardless of our individuality.