It depends. It depends on you, on your state of consciousness or unconsciousness, whether you are asleep or awake. Happiness will depend on where you are in your consciousness. If you are asleep, then pleasure is happiness. Pleasure means sensation, trying to achieve something through the body which is not possible to achieve through the body, forcing the body to achieve something it is not capable of.
People are trying, in every possible way, to achieve happiness through the body. The body can give you only momentary pleasures, and each pleasure is balanced by pain in the same amount, in the same degree. Each pleasure is followed by its opposite. It is a vicious circle. Your pleasure will be followed by pain, your pain will be followed by pleasure. But you will never be at ease. When you will be in a state of pleasure you will be afraid that you are going to lose it, and that fear will poison it. And when you will be lost in pain, of course, you will be in suffering, and you will try every possible effort to get out of it – just to fall again back into it. He lives from one pleasure to another pleasure. He is just rushing from one sensation to another sensation. He lives for small thrills. His life is very superficial; it has no depth, it has no quality. He lives in the world of quantity. The non-meditator sleeps, dreams; the meditator starts moving away from his sleep towards awakening.

Then happiness has a totally different meaning: it becomes more of a quality, less of a quantity; it is more psychological, less physiological. He enjoys music more, he enjoys poetry more, he enjoys creating something. He enjoys nature, its beauty. He enjoys what he had never enjoyed before, and this is far more lasting. Even if the music stops, something goes on lingering in you. And it is not a relief.

But this is also not the ultimate. The ultimate happens only when you are fully awake, when you are a buddha, when all sleep is gone and all dreaming is gone, when your whole being is full of light, when there is no darkness within you. All darkness has disappeared and with that darkness, the ego is gone. All tensions have disappeared, all anguish, all anxiety. You are in a state of total contentment. You live in the present; no past, no future anymore. You are utterly here and now.
Pleasure is animal, happiness is human, bliss is divine. Pleasure binds you, it is a bondage, it chains you. Happiness gives you a little more rope, a little bit of freedom, but only a little bit. Bliss is absolute freedom. You start moving upwards; it gives you wings. You are no more part of the gross earth; you become part of the sky. You become light, you become joy.

Pleasure is dependent on others. Happiness is not so dependent on others, but still it is separate from you. Bliss is not dependent, is not separate either; it is your very being, it is your very nature. To attain it is to attain nirvana.