The warning note was sounded by psychiatrist Anthony Clare. On Thursday, the third day of the Oireachtas Committee on the Constitution's abortion hearings, Labour TD Ms Liz McManus suggested that Irish society had moved on from the bitter divisions of other days.
Prof Clare told the TDs and senators that because people were so reasonable in the debate before the committee, it did not mean the steam had gone out of the issue.
He reminded them that the extremes were articulated powerfully in a bulky briefing document supplied by the committee, adding that abortion touched something very basic in the heart of every Irish person.
Many politicians privately agree with Prof Clare. Abortion is still a bitterly divisive issue. The committee, under the chairmanship of Fianna Fail TD Mr Brian Lenihan, had a good first week. Politics has been put aside and the questioning of the witnesses is, by and large, incisive.
The committee will finalise the medical evidence next Tuesday and later hold hearings for interested groups. A recommendation is expected to be made to the Government in the autumn.
While the atmosphere at the hearings is constructive and civil, reaching a consensus on the issue is likely to be very difficult. Sharp differences have emerged so far in the medical evidence.
Dr Declan Keane, of the National Maternity Hospital, said most of his colleagues would be "conscientious objectors" if abortion was legalised. Dr Peter McKenna, of the Rotunda Hospital, warned that placing a constitutional ban on abortion would mean somebody's life would sooner or later be put at risk. Prof Clare argued that rape and incest victims should have the option of a legal abortion in Ireland, while a leading paediatrician, Dr Brian Denham, argued for restricted abortion.
Dr Eamon O'Dwyer, professor emeritus of obstetrics and gynaecology at NUI Galway, said he had looked after over 9,000 women in a 40-year career. "Not one of those 9,000 women died, and I never had reason to think that I could have done better if I had abortion."
Meanwhile, the Government is under pressure from two of the Independents helping to keep it in power - Ms Mildred Fox (Wicklow) and Mr Harry Blaney (Donegal North East) - to hold an abortion referendum.
Prof John Bonnar, chairman of the Institute of Obstetrics and Gynaecology, wants a referendum, but admits that finding a wording could be difficult. A "simple soundbite of a half-dozen words" would not be adequate, he told the committee, adding that the Oireachtas should put legislative proposals to the people. Politicians doubt this is practicable.