Before any facts about the perpetrators of the Paris attacks could be discovered many politicians here were already jumping to conclusions. The governors of 17 states jumped to the conclusion that the perpetrators were Syrian refugees and used that to declare their states closed to any refugees from Syria. But an investigation into the attackers turned up evidence that they were European nationals:
“Let me underline, the profile of the terrorists so far identified tells us this is an internal threat,” Federica Mogherini, the High Representative for Foreign Affairs and Security Policy/Vice-President of the European Commission, said after a meeting with EU foreign ministers. “It is all EU citizens so far. This can change with the hours, but so far it is quite clear it is an issue of internal domestic security.”
My point isn’t that the attackers were carried out by European nationals. The investigation has just begun so other evidence could indicate the attackers were indeed Syrian refugees or trained members of the Islamic State of Iraq and the Levant (ISIS) who snuck into France or shapeshifting lizard people from another dimension.
My point is that jumping to conclusions before an investigation has come to a conclusion supported by solid evidence is foolish. Be smart. Wait for evidence to be discovered before telling everybody what you think happened.