For the present, however, let us see what can be said about it from that standpoint of positive science to which we have hitherto been keeping.
Now, if by common be meant what has been shared by all minds or the majority of minds up to a particular time, a moment's inspection of the process of correcting illusion will show that science assumes the possibility of a common illusion.

In the history of discovery, the first assault on an error was the setting up of the individual against the society.

The men who first dared to say that the sun did not move round the earth found to their cost what it was to fly in the face of a common, though illusory, perception of the senses.[151] If, however, by common be understood what is permanently and unshakably held true by men in proportion as.