I would say you are correct. The way I see this text is where the assumption must be strictly true for the statement to hold.Quick WG Assumption Q:
For humankind to survive, it must colonise other planets.
Assumption - There will be a time when the Earth can no longer sustain human life.
Am I right in saying that an assumption has been made here?
The only thing I can think of against this is that Earth may very well sustain human life, but not be sufficient. Then again, that would mean that it technically cannot sustain human life, and therefore, the assumption is made.
Also, if I were to invert this: There will be a time when the Earth can sustain human life, then the proposed statement becomes redundant, which should logically indicate that there is an assumption, no?
3.30 am yk, I hate these damn tests.
Therefore, for the statement "There will be a time when the Earth can no longer sustain human life." an assumption has been made that Earth would not be able to sustain human life in perpetuity, i.e., if it could, there would be no reason to colonise other planets. In other words, given that human life is definitely not going to support human life forever, it *must* colonise other planets to ensure survival.