Pleasure is an experience at physical level. An example is when you are seated comfortably in a cushioned chair that gives your body a relaxed feeling. This is called pleasure. Happiness is an experience at mental level. An example is
What is the source of ‘Aanandam’, the bliss
None of them have the ability to independently give you a permanent state of bliss. That state of bliss lies when you raise above all of these and connect yourself with that Super power, who is the true source of