Economic logic goes missing

Sir, – Ian Blackford, the SNP Commons leader, has renewed his attack on Boris Johnson as a “walking advert” for independence, when the prime minister visited Scotland yesterday.

Indeed, that about sums it up, doesn’t it?

The SNP argument for separating us from the rest of the UK can be found not in rigorously thoughtthrough, clearly articulated nationalist dogma nor in irrefutable economic logic, but in relentless ad hominem attacks on the prime minister of the day, who may not be with us much longer.

Work to do, Mr Blackford? Martin Redfern. Melrose, Roxburghshire.