The speaker begins with a puzzling claim: nothing in their heart is beyond their understanding, yet the rest of the poem suggests how much remains unreadable. The "conspiracy of lines" on the palm hints at fate, as if the body itself were plotting against hope, and dreams are "aborted" before they can grow. Even the face gives nothing away. It doesn't reflect the nightmares that haunt the speaker, so inner turmoil stays hidden behind an ordinary look.
In the closing lines, the speaker keeps "getting taller" and walks over shadows that "seek identity." The shadows seem to stand for the darker, unformed parts of the self, or perhaps the past, which want recognition. The speaker doesn't stop for them. The mood is guarded and quietly bitter, a mix of defiance and weariness. Growth and success are possible, the poem suggests, but they may come by stepping past the things we haven't resolved.