This is the 1500th most frequent Japanese word.
そのもの
"そのもの" means "the thing itself" or "itself."
The phrase "感動そのもの" here shows "感動 (moving)" in an emphasis form, meaning it was pure and absolute moving.
彼のスピーチは感動そのものだった。
His speech was moving itself.
The term "真理そのもの" literally means "truth itself," indicating that the philosophy is dedicated to the essence of truth.
それは真理そのものを追求する哲学です。
This is a philosophy that pursues truth itself.
"芸術そのもの" suggests that the painting embodies the pure essence of art, emphasizing its artistic nature.