I agree the post is muddy about whether the relationship is bijective (equivalent, poodle=dog) or injective (onto, poodle is a dog). I make it slightly more precise in the statement "I posit that open source software is a necessary condition if we are to science in a computerized world". That's where the "is" comes from in the title. Throughout history, this definitely has not been the case. I'm arguing that's changing.