A statement is something like a biography or autobiography, where a person tells about the likings and goals of somebody.
A personal statement of Lewis could be reading. He, in his autobiography, that his house wass filled with books, and that all he neede was a rainy day to start reading them.
And, by looking at his books you can see he was interestid in, and interested in writing about nautre and philosophy.
Hope it helped,
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