Isaac Newton as a philosopher

As amazing as his science was, some of his assumptions about the natural world were deeply flawed. Newton was a frequent alchemist. One of his ultimate dreams was to finally figure out how to make gold. We know in the modern day that alchemy is essentially a made-up science (something not really known in the day), but despite his incredible contributions to mathematics and science (both 10s, in my book), I feel that I cannot rate him higher than a 6 or a 7 (I chose a 6) in philosophy because of this.