He said it was too early to say conclusively that the boy was making a bomb when the blast occurred.
And no one knows enough about the habits of app readers to say conclusively how engaged they are while browsing through a digital magazine.
Mr Mazzini, whose team has studied mud volcanoes for more than a decade and spent just under a week on site, said it was impossible to say conclusively whether the drilling caused the disaster.
There is now enough credible evidence to say conclusively that drinking is a direct cause of the disease, according to Jennie Connor, of the preventive and social medicine department at Otago University in New Zealand.
And though it is too soon to say conclusively, experts theorized on Friday that ice, one of aviation's most common problems, could indeed have brought the plane down.
Even with a study as rigorous as this, it is impossible to say conclusively whether the women lost weight because their salaries rose, or whether their salaries rose because they lost weight.
As a result, we are unable to say conclusively that CeD4TEA emits no photoluminescence when excited.
KBA does not report all details of the tested vehicles, so it is difficult to say conclusively what technologies are used in the engines and emission-control systems.
"It is too early to say conclusively," said Dr. Carol Foyler, head of the team of doctors who examined the vice president.
It's impossible to say conclusively whether all of these deaths are justified, but if I'm going to speculate, the overwhelming likelihood is that they're not.
"It is difficult to say conclusively whether a specialized sexual assault court would offer the kind of reform necessary to prevent the victim-blaming culture that infiltrates sexual assault proceedings," she says.
