Well spotted! I posted that link in 2014, I think the contents of the page have since changed … the speaker Algimantas is clearly not a native speaker of Swedish. Forvo is starting to go bad from some very active non-native speakers who record a lot of sentences. The speaker arhus12 sounds perfect though.
Yes. It is confusing... also then we Scandinavians have to learn English. But languages have different ways to use the definite articel.
In English, it is normal that general ideas as Science, Nature and Heaven have no articel or 'the'. But in Swedish (and Danish), we often prefer to write Vetenskapen (videnskaben), Naturen and Himlen with the definite article.