He said: “Yes, I think we are. The question is how big that third wave is – everybody, every modelling higher education institution… they all said, if you open you will get more cases.
“Now I’m not sure I needed a university to tell me that, I think people in the street would have told me that.
“The question is, whether you control that to a level that doesn’t cause enough severe disease to fill hospitals, and enough severe disease to cause misery and death to families.
“That’s the balance we’re now trying to strike and the advice we’ve given and the decisions the First Minister and the Cabinet have made today.”
On Tuesday, the First Minister announced tougher lockdown rules or areas affected by the Indian coronavirus variant – now officially known as the Delta variant.
Areas such as Glasgow will not be able to move into the next level of lockdown lifting.
Scotland was due to transition into Level 1 measures from June 7.
The new guidelines would enable up to eight people from three households to meet indoors in pubs, cafes and bars.