Brendan Keenan: Even if the professor's sums were wrong, we still need answers
SIZE matters. There is all the political and policy difference in the world if it is 44pc or 10pc of people with young children who would be better off not working.
But it is not everything. The unprecedented row over the ESRI working paper on the costs of working raises important issues, irrespective of the number. They include costs in the economy, social welfare policy and how public debate is conducted.
On a day when the troika's latest progress report surfaced, it even has a bearing on the fears that, even though we are two-thirds of the way there, Ireland may not succeed in its programme to fix the public finances.