Our behavior can change what we like and dislike. Although it seems clear that we might like something more when we smile (versus frown), or when we nod our heads (versus shake), it is important to understand the processes responsible for these changes in evaluation. It might be that agreement behaviors such as smiling and nodding work as cue, make us think about everything in a positive light, or it might be that they encourage us not to think much about the information we receive. This review describes the basic processes underlying embodied change, highlighting the role of a recently discovered meta-cognitive process (called self-validation) by which bodily responses can validate or invalidate (instead of changing) our thoughts. This new mechanism can account for some already established outcomes in embodied persuasion (e.g., more persuasion with smiling than frowning), but by a different process than postulated previously (smiling increases confidence in thoughts), as well as for some new findings (e.g., more persuasion for low than high powerful postures; more self-confidence when performing doubtful postures).