If you closely observe what happens, you’ll notice that coming out of drowsiness is distinctly unpleasant. You would probably prefer to stay there. However, by resisting the urge and returning to the practice, you’ll usually experience a comfortable state where you can still follow the breath, though without the same intensity or vividness or clarity as before. This is called subtle dullness. It eventually leads to strong dullness, in which attention still clings to the breath, but the focus is weak and diffuse, and the sensations vaguely perceived.
