As already stated earlier, the 32 piano sonatas form the New Testament for the instrument. These two squarely belong to the early period. Beethoven was still trying to find himself, and did so in his opus 2 by looking at his master Haydn. The result, composed in 1795, is a work fitting the classical style. Beethoven’s fourth piano sonata is already more on his own footing. In 1797, we find Beethoven slowly making inroads towards a much more romantic world. Here he finds a new world in the genre of the piano sonata, and is starting to experiment with it.
For my personally Beethoven really gets my interest nearing the end of his life, when his struggle can be found all over in his music. Both of these works are still too classical for me.