For comparison , I think that water in a lake has properties of a cloud while not being a cloud . I also think that a wooden table has properties of a tree while not being a tree . So , I can see this viewpoint as an explanation . But , I would also suggest it possible that Ernest Rutherford had another meaning for radio-active .

I would also suggest it possible that Ernest Rutherford had another meaning for radio-active .

 

That's what I had suggested. Rutherford's definition may not be the same as the modern definition; we know more. We should use the modern definition that has the benefit of the application all that extra knowledge.

 

By the modern definition, alphas, betas and gammas are not radioactive.