Franz Liszt was a composer-pianist (largely). He transcribed Beethoven's symphonies for piano. Beethoven was a composer.
Wagner and Tchaikovsky were composers. Haydn was a composer and a teacher to Beethoven. Knowlede about Liszt's transcriptions here.
The idea of Franz Liszt to play Ludwig Van Beethoven on piano was to show that Beethoven had a soft touch in all the symphonies. Franz's piano played the part of bringing to notice the absolutely sublime part of the music; sublimity also defined as softness; that which does not hurt the ears; that which replaces the alleged harshness of trombones and trumpets.
Any music listener would need to imagine music and 'circumstance' to essentially be in touch with classical music. I define circumstance as supreme imagination. All are not lucky to possess this imagination.that
It is thus that Wagner, Tchaikovsky saw in Beethoven what others didn’t. Also, this circumstance of superior imagination may come now and then, making the task of the critic obsolete since there is no absolute to music except that which is easily seen as horrendously bad.
The listener, say, like Haydn, may one day, at an opportune moment accept that what he had previously considered as mediocre is essentially life-changing; like Haydn alluded to Beethoven’s music after listening to his Symphony no.3.
Is it not a pleasure to listen to an orchestra play Beethoven’s works, and then listen to Liszt play them on the piano? You realise that music has shades, a statement passed of as obvious by music lovers, but which assumes greater significance for the listener when faced with the actuality of listening to the soothing piano tones after the absolute power of the trumpets and the string section.
The listener, now, has to imagine the power displayed by the trumpet in the notes of the piano. A task that is of great love to the listener. A task that may define the mysterious emotion of 'love'. For love is this deeper imagination of music, and hence of life.