Source: p 120, The Law of Contract, 5 ed (2012), by O’Sullivan and Hilliard
Promissory estoppel cannot take the place of consideration when a contract is being formed for the first time between the parties, only (as in the Foakes v Beer problem) when existing contractual rights are being varied. Denning J did not emphasise this restriction in High Trees (although, of course, the landlord’s representation there[,] was as to existing legal rights—the right to claim the full rent) but it has been applied ever since. Brennan J regarded this restriction as ‘illogical’ in Walton Stores v Maher (see para 6.86): ‘If a promise by A not to enforce an existing right against B is to confer an equitable right on B to compel fulfilment of the promise, why should B be denied the same protection in similar circumstances if the promise is intended to create in B a new legal right against A?’
1. Please explain and simplify Brennan J's quote in the last 3 lines?
2. Specifically, I don't understand the bolded part. Once 'an equitable right' is conferred 'on B', who's compelling the fulfilment? Who's the promisee here?
3. What in the quote implies that B would 'be denied the same ... right against A?' I ask not about law, but need to infer Brennan's analogy supporting B against from his quote, yet his writing besets me.