Learn Italian: Pur sapendo la verità, non si arrende. - Despite knowing the truth, he does not give up.

In Italian, combining pur with a present gerund (like sapendo, from sapere) creates an implicit concessive clause. It is a concise way to express 'even though' or 'despite' doing something. It means 'despite knowing' in this sentence.

Can I use anche se (even though) instead of pur to express the same idea?

Yes, but anche se requires a normally conjugated verb rather than a gerund. You would have to say anche se sa la verità (even though he knows the truth). Using pur sapendo is slightly more elegant and works perfectly here because both actions share the same subject.

What is the infinitive of si arrende and why does it need si?

The infinitive is arrendersi (to give up or to surrender). It is a reflexive verb in Italian, so it requires a reflexive pronoun. Since the implied subject is 'he' or 'she', we use the third-person reflexive pronoun si.

How do we know who is knowing the truth, since sapendo doesn't tell us?

A strict rule of using pur with a gerund is that the subject of the gerund must be exactly the same as the subject of the main sentence. Since the main verb si arrende tells us 'he' (or 'she') gives up, we automatically know that the same person is the one who knows the truth.