In that article, from an 80 old day comment of mine, you did not understand my comment. You told me to read the article. You don't understand what I mean by justification. There is a difference between prescription and description. That article was descriptive, not prescriptive. You cannot justify universals if you believe only particulars exist. You can only justify universals if you are willing to accept a metaphysical reality and provide a grounding for the metaphysical. Not everything is proven in the same way. The scientific method is good for studying particulars, but it cannot prove a universal. For example, science assumes the laws of logic in its process, which it cannot prove or provide a justification for. Also the scientific method cannot justify the scientific method. You on the other hand will probably say "because it works." Something working is a value-judgement, and that is not independent of ethics. It also assumes induction and regularity in nature, but you obviously haven't heard about the problem of induction. Science cannot provide a justification for induction. Science will also claim things like we know things from observation or what is in the sense data. Did we observe that or sense that in our sense data? I would say not everything is proven the same way. You can use science for some stuff, but not everything.
