I think that website cheats a little bit. The first link in "Science" is not "Knowledge" but "Latin", where it's describing the root of the word "Science". If you follow it properly, you'll find that even the article for "5 Whys" doesn't go to Philosophy:
5 Whys
Technique
Technology
Tool
Goal
Animal
Eukaryote
Organism
Biology
Natural Science
Science
Latin
Italic Languages
Indo-European Languages
Language Family
Language
Human
Taxonomy
Ancient Greek
Greek Language
Indo-European Languages // Infinite loop!