The embodiment thesis is not merely a correction to one wrong philosophical theory. It ripples out into almost everything, how we understand language, art, and the puzzle of other minds.
Language: On the Cartesian view, language is basically email. You have a thought (the content); you encode it in words (the message); you send it; the receiver decodes it back into a thought. The words are just the packaging, in principle lossless, in principle replaceable with any other packaging that carried the same content.
For Merleau-Ponty, this is completely wrong. Speaking is not encoding a thought, it is a gestural act through which thought is constituted. The thought takes shape in the act of expression; it doesn't preexist the words waiting to be packaged. This is why poetry cannot be paraphrased without loss, the form is not packaging for a separable content, it is the content. The rhythm, the sound, the particular choice of word: these are not ornamental. They are where the meaning lives. You feel this when you search for a word, you are not searching for a label for a fully formed thought, you are searching for the word that will complete and clarify the thought that is still only half-formed.
Painting: Merleau-Ponty's last published essay, Eye and Mind (1960), meditates on what painting reveals about being a body in the world. Painters like Cézanne fascinated him because their work shows that seeing is not passive recording, it is an active, bodily engagement with the visible world. Cézanne's apples feel massive and present in a way that photographs don't, because Cézanne was not copying what he saw but expressing the lived quality of looking, the weight and density that a body feels in the presence of substantial things.
Other people: The hardest problem for Cartesian philosophy is the problem of other minds. If consciousness is locked inside each individual skull, how do you know that other people have inner lives at all? Merleau-Ponty's embodied account dissolves the problem by transforming its terms. You don't infer other people's inner states from their behavior and then analogize from your own case. You directly perceive the expressivity in their face, their gesture, their posture, because their body and your body are both modes of the flesh, speaking a common language. When someone winces in pain, you don't deduce their pain from their face, you see it. Intersubjectivity is built into the structure of embodied perception from the start.