Her insights and quotes were wise too. The best and most beautiful things in this world cannot be seen or even heard, but must be felt with the heart - Helen Keller.
The content of the OP is wise insights and quotes. Tim's contribution is in the same vein - particularly poignant because of the reference to sight versus touch.
There is another sensory system, that is much less understood. Felt in the heart is not a metaphor, but rather it is based on being aware of subtle electrical based tweaks in the heart, and other parts of the body, that you can feel, that often coordinate with thoughts. If I am not mistaking the Chinese once thought the liver was the seat of consciousness. This was due to gut feelings, instead of heart based feelings. We can't feel the brain working, but can be infer by its sensory nerve feedback loops in the gut and heart and other places. If you feel love in your heart, there is certain sensory feedback signal in the heart connected to the brain. Beauty also has a certain heart buzz. There is a natural language to this. Helen Keller developed this extra sensory awareness to compensate for her lack of sight. I come up with a lot of idea and often get little feedback from others beyond indifference or negativity. So I make use of the sensory loops to get feedback. Even without seeing the hard data of reality, Helen Keller could us the loops to develop wisdom. I am blind; metaphorically, due to lack of resources, so I developed this skill too; improvise. It is a fast language and is not always easy to be perfect.
Unfortunately, these can't be classified as senses. It is the the brain that senses beauty and other external stimuli (through sight or smell, etc), and in response, it sends out signals to the organs, such as telling the heart to beat a little faster or causing the stomach to contract. While you certainly can feel your heart or stomach flip flop - it is not a sense, since its source is internal (the brain) not external (the world out there)