Complex sentence: This assumption of responsibility on the part of the speaker is described by Habermas as a "warranty", because in most cases the validity claims raised during communication are taken as justified, and communication proceeds on that basis.
Split into simpler sentences: This assumption of responsibility on the part of the speaker is described by Habermas as a "warranty". It is described as a warranty because in most cases the validity claims raised during communication are taken as justified, and communication proceeds on that basis.