At your time of life the knowledge cannot come from observation.

But they had not come from her research or observations.

I asked him, since he had such a knowledge of men from observation, why this was so.

All I can say from my own observation is this.

I had thought so, from my own observations last summer, but the little ones never sat still for long.

But she knew from experience and observation that this was not the way of a man.

They were safe from observation by those on the street.

The two men knew that they were safe from observation.

These times have been established from observations over a period of years and are for an individual at rest.

"So this is no more than your opinion from personal observation?"