He argues that rationality requires some goal to work towards, and selfishness doesn't contradict rationality, rather it applies rationality to one's own self-interest. On the other hand, Subhra et al. proposed an efficient countermeasure for mitigating griefing attacks in Bitcoin-compatible PCNs, known as Griefing-Penalty. Their contribution includes proposing a new payment protocol called HTLC-GP or Hashed Timelock Contract with Griefing-Penalty, which compensates the honest nodes for their loss due to griefing attack. All the parties affected by griefing must get compensation since their liquidity is tied up for a certain period of time. In summary, ZmnSCPxj argues that Griefing-Penalty cannot prevent Reverse-Griefing attacks without causing Griefing attacks, while Subhra et al. proposed an efficient countermeasure for mitigating griefing attacks in Bitcoin-compatible PCNs, known as Griefing-Penalty. A proposed countermeasure to mitigate griefing attacks in Bitcoin-compatible payment channel networks (PCNs) has been presented in a recent paper titled "Griefing-Penalty: Countermeasure for Griefing Attack in Bitcoin-compatible PCNs". The authors propose a strategy called "Griefing-Penalty", which compensates intermediaries affected by the attack. The authors illustrate the benefit of the proposed countermeasure with a new payment protocol called HTLC-GP (Hashed Timelock Contract with Griefing-Penalty), and provide a security analysis that proves the protocol is privacy-preserving while mitigating losses due to griefing attacks by compensating honest nodes. To penalize adversaries, the authors propose an off-chain contract established between two parties where both parties lock funds, with one party locking the amount to be forwarded and the other party locking the fund claimable as a penalty if it grieves. The penalty locked is proportional to the product of the amount being forwarded and the expiration time of the contract, and all parties affected by griefing must receive compensation since their liquidity is tied up for a certain period. An example was demonstrated where A wants to transfer 1 msat to C, but funds remain locked if C grieves. By modifying the contract, the authors term it HTLC-GP, where a rate of penalty (0.01 per hour) is used for calculating the penalty the party has to lock to accept an off-chain contract request. If C releases the preimage before the expiration of locktime, it will claim the full amount locked in the contract. In contrast, if C grieves, B must ask C to lock funds in the contract, which can be used for compensating both B and A. If C grieves under this condition, it loses 0.72 msat (proportional to the collateral cost of the path).