What does Steffen mean by "On the one hand we have the unthinkable, and on the other hand we have the unimaginable"?

What Steffen meant by "On the one hand we have the unthinkable, and on the other hand we have the unimaginable" is:

There are worst-case scenarios which are as a result of the planet depletion. These effects are known to be unthinkable. Then the alternative is the unimaginable which is something we are yet to know. The environmentalists are working towards the unimaginable but are yet to grasp it. Whereas as the planet experiences a downward trend then the unthinkable is what will happen.

Explanation:

Alex Steffen, in his TED Talk in 2015, spoke on "The Route To Sustainability".

He revealed the state of our planet and the activities being carried out that led to its current. Also, he revealed the need for green cities if sustainability must be achieved in our planet.

no it is not a sin or wrong to be gay. you can be whoever you want just dont hurt anybody or kill anybody. god gave us freewill so we could do whatever we want and be whoever they want to be. all those other people who think gay is bad they are wrong, they can love whoever they want longs they don't hurt or kill each other.

being gay is not a sin or wrong. if you are gay then you have our support and love. cause lets face it, love is love and no bully will ever stop us from being who we are. we are human and we can be different. being different is what makes us humans.

its okay to be gay everyone.

hope this : )

have a great day