Raising social security grants more generously could tempt unemployed people to fraudulently seek disability grants.
This was the view expressed by Finance Minister Trevor Manuel before the portfolio committee on finance in parliament on Thursday.
In replying to a question from one of the members of the committee, he justified his decision to raise social security grants for pensioners and disabled people by R40 to R740.
Manuel said more generous increases could be a disincentive for people to look for jobs as being disabled could suddenly appear relatively lucrative.
"Currently, people in the domestic and agricultural industries receive minimum salaries of, er, about R600."
"Now why would anyone want to work (if you know that even when you work you are not likely to earn more than a pensioner or disabled person)?" asked Manuel.
The finance minister said there was a balance to be maintained.
He cautioned against "unwittingly" encouraging people to seek illegal means of getting hold of disability grants.
Manuel's comments follow stinging opposition attacks on the increases he announced during the reading of his Budget speech on Tuesday.
Child support grants were raised by R10 to R170 a month. The Pan Africanist Congress of Azania's Motsoko Pheko said the increase was a mockery.
The social development department had in the past experienced numerous problems with what it termed "ghost" beneficiaries.
But the manner in which the department had dealt with them had generated numerous contestations.
Last year, the Legal Resources Centre (LRC) took the department to court for allegedly removing the names of beneficiaries without warning them.
In court papers, the LRC said it was displeased with a decision to remove a large chunk of people's names from the roll.
Police have also arrested a number of people, including teachers, who had allegedly fraudulently claimed for child support grants.
In a brief interview with the Cape Times after the committee meeting, Manuel explained that it was well and good for people to call for increases in social security grants.
He said the amounts were being offered to people "for doing nothing".
"What I am saying is that - why would I work?"
Manuel's views tie in with the thinking of President Thabo Mbeki who has often said that South Africa ought to create an economy in which its many citizens actively took part rather than relied heavily on social security grants.