Union Minister Arun Jaitley today took a jibe at the Congress, saying the party has "proved that in dynastic parties, ignorance is contagious". Addressing the media after a briefing for Council of ministers on the French deal, Mr Jaitley combined a sharp attack on the Congress and its chief with a reiteration that there was no way any private firm could benefit from the deal, since "not a screw is to be fitted in India".