Answer: if you are very serious, and you should, the universal can only be used for what belongs essentially to a concept, as concept, and not as refering itself to something. The general applies to whatever belongs to the empirical world. (Thus also, statements.)
This differentiation has provoked great troubles all along history because of the difficulty for a common human to make the difference between a concept and its object. But see, the concept is in your mind, and the way it appears and it is perceived, has nothing to do with what appears through senses. If you say « fingers are parts of the body belonging to the hand » it is universal (definition through category). But if you say « humans have 5 fingers », if refering to the outer reality, there may be some having only 4, or 2, or none, thus, it can only be a general statement, while as determining the nature of the human in concept it may be considered a universal statement.
Thus, the universal is only a priori, as the facculty to discern an essence out of a notion is not depending on senses but on what could be called perhaps ‘spirit’ or ‘forms of reason’ (Kant) or ‘understanding’ (Hume). This very simple differentiation may have avoided gravest quarrels between empiricist and idealists, as I’m sure, Hume, who refuses to accept a universal for what comes of senses, would have never refused the evidence of the universal inherent to concept, even if he maintains with Aristotle, that the ‘universality of concept’ does derive from a repetition of the sensitive impression on the mind, and thus, may have put a barr quite quickly to Kants pretension you may through principle admit a universality in nature that justifies truth in science.
But what. Shall there be nothing to be improved in metaphysics?