NICK Clegg is pursuing his idea for a mansion tax. “That’ll show them pesky rich people!”

But I think I’m missing something. He told Radio 4 this morning:

Actually our change increases the value of the mansion tax, it actually increases the amount of money that you would generate because not only are we doubling it to £2m, we’re doubling the levy from half a per cent to one per cent.

You see what he did there? He said  that “not only” is the tax to be levied on houses worth £2 million and above (the previous threshold was £1 million) but the per centage rate is to be doubled. It’s the “not only” which is confusing me, because that should only be used if you’re describing two different things which reinforce each other’s meaning. For example:

The LibDems are not only political opportunists, but they also have bad dress sense.

So Clegg seems to be saying that the amount of money the mansion tax will raise will be increased because of two factors: the value of homes on which it will be levied is higher than the previous plan AND the per centage rate is also doubles.

Sorry if I’m labouring the point here, and it wouldn’t be the first time I’ve missed somethng obvious. But surely if you’re raising the threshold at which the new tax takes effect – doubling it, in fact – you’re also significantly reducing the actual number of homes on which the tax can be levied, thereby reducing the tax take?

So either Clegg was misleading listeners into believing that both changes to his scheme were aimed at increasing the tax take, when in fact one would decrease it and the other increase it; or I’ve got the wrong end of the stick completely.

Can anyone shed any light on this?