The hereditary House of Lords has a constitutional basis, however dim and distant, in the old hierarchy of monarchy and aristocracy. Because this basis remained intact the Lords were able - just about - to absorb the creation of life peers. However an entirely appointed second chamber such as the Government now proposes would have no constitutional or moral justification at all.
Since the hereditary principle has had its day, the only defensible basis for a second chamber now is direct election. Better still, we need a chamber detached from the politics and timescale of the House of Commons. It should be elected for a fixed term of five or seven years and by proportional representation, a principle which the Government has already conceded by implication when it talks about rough balance between Labour and Tory peers in an appointed House of Lords.
Of course such an elected chamber would have to be given real powers. There is scant chance that any government - especially the present one - or the Commons would agree to that, so it looks as though the basic issues of principle, which are really very simple, will continue to be dodged.