When meditators' minds have reached genuine happiness in the dhamma through their mindfulness and discernment, clearly seeing the four noble truths, none of them—not one—will revert to looking for happiness in the world or in material things. That's because happiness in the dhamma is a lasting happiness: solid, refined, and genuinely pure. If you compare worldly happiness with the happiness of the dhamma, you'll see that there's not even the least real happiness to it. It offers nothing but stress, nothing but drawbacks. So why do we think it's happiness? Because we're burning with pain. We look to worldly happiness and pleasures to relieve the pain, which then goes away for a while but then comes back again.