why gaining partner compensate to sacrificing partner only through GOODWILL?

As we know that at the time of reconstitution of partnership firm all the adjustments related to accumulated profits and losses, goodwill, etc. are required to be made. In case of change in profit sharing ratio, there can be a scenario where one partner gains whereas another partner sacrifices. Thus, in order to compensate the sacrificing partner, the gaining partner will pay the proportionate amount to the sacrificing partner for the share sacrificed. 

This is the basic logic because of which we debit Gaining Partner's Capital A/c and credit Sacrificing Partner's Capital A/c. 

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