I think there’s some looseness in the Mind Illuminated ontology around this point, but I would say: thinking involves attention on an abstract concept. When attention and/or awareness are on a thought, that’s metacognitive attention and/or awareness. For example, if I’m trying to work on an intellectual task but start thinking about food, my attention has moved from the task to food. Specifically my attention might be on a specific possibility for dinner, or on a set of possibilities. If I have no metacognitive awareness, then I’m lost in the thought; my attention is not on the thought, it’s on the food.
I think there’s some looseness in the Mind Illuminated ontology around this point, but I would say: thinking involves attention on an abstract concept. When attention and/or awareness are on a thought, that’s metacognitive attention and/or awareness. For example, if I’m trying to work on an intellectual task but start thinking about food, my attention has moved from the task to food. Specifically my attention might be on a specific possibility for dinner, or on a set of possibilities. If I have no metacognitive awareness, then I’m lost in the thought; my attention is not on the thought, it’s on the food.