“A controversy has arisen about this: whether it is better to be loved than feared, or vice versa. My view is that it is desirable
to be both loved and feared; but it is difficult to achieve both and, if one of them has to be lacking, it is much safer to be
feared than loved."
Nicolo Machiavelli, The Prince, 1532
This quotation is taken from a book that is associated with what era in world history?

No it is an oblate spheroid apparently

This is all you, but i can give you some topics that you could try. if it rained when you want to do something outdoors, it 'limits' that human activity. maybe you want to do an experiment that goes throughout the whole year and you have to have above freezing the entire year. this 'limits' your activity. i thought of those just off of the top of my head. something that gets to me that might be getting to you is you are thinking too hard about what to do. think simply, and if it is too simple, then bump it up just a little bit.