Consider:
学生のようだ。
Without additional context can this statement mean both:
- He looks like a student. i.e. he has the stereotypical appearance of a student; he's wearing glasses, has a studious look, and appears not to have washed for a week. It could be that I know he is not a student. I'm just saying that he looks like one.
- He seems to be a student. i.e. judging by the evidence I believe that he is in fact a student. He doesn't necessarily have the appearance of a student, but the evidence points to him being one.
Can we rule out either of these possibilities grammatically, or is it purely down to context?