I'm afraid it's not that simple. Unconscious, or unconsciousness, describes a state, e.g. to be unconscious, and thus can also describe the state of a thought, e.g. we are not aware of our unconscious thoughts. Subconscious however, is only used to describe an unconscious thought that has a conscious effect, for example, seeing food can subconsciously make us hungry, or a deep seated childhood trauma could subconsciously effect our decision making process.

Shmuls,
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